Compositions and methods for binding sphingosine-1-phosphate

ABSTRACT

The present invention relates to anti-S1P agents, for example, humanized monoclonal antibodies, and their uses for detection of S1P or for treatment of diseases and conditions associated with S1P.

RELATED APPLICATIONS

This application is a continuation-in-part of, and claims the benefit ofand priority to, U.S. non-provisional patent application Ser. No.11/924,890 (attorney docket no. LPT-3010-UT), filed on Oct. 26, 2007,and its priority application, U.S. provisional patent application Ser.No. 60/854,971 (attorney docket no. LPT-3010-PV), filed on Oct. 27,2006, the contents of each of which are herein incorporated by referencein their entirety for any and all purposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to agents that bindsphingosine-1-phosphate (S1P), particularly to humanized monoclonalantibodies, antibody fragments, and antibody derivatives specificallyreactive to S1P under physiological conditions. Such agents can be usedin the treatment and/or prevention of various diseases or disordersthrough the delivery of pharmaceutical compositions that contain suchagents.

The following description includes information that may be useful inunderstanding the present invention. It is not an admission that any ofthe information provided herein, or any publication specifically orimplicitly referenced herein, is prior art, or even particularlyrelevant, to the presently claimed invention.

2. Background

Bioactive Signaling Lipids

Lipids and their derivatives are now recognized as important targets formedical research, not as just simple structural elements in cellmembranes or as a source of energy for β-oxidation, glycolysis or othermetabolic processes. In particular, certain bioactive lipids function assignaling mediators important in animal and human disease. Although mostof the lipids of the plasma membrane play an exclusively structuralrole, a small proportion of them are involved in relaying extracellularstimuli into cells. “Lipid signaling” refers to any of a number ofcellular signal transduction pathways that use cell membrane lipids assecond messengers, as well as referring to direct interaction of a lipidsignaling molecule with its own specific receptor. Lipid signalingpathways are activated by a variety of extracellular stimuli, rangingfrom growth factors to inflammatory cytokines, and regulate cell fatedecisions such as apoptosis, differentiation and proliferation. Researchinto bioactive lipid signaling is an area of intense scientificinvestigation as more and more bioactive lipids are identified and theiractions characterized.

Examples of bioactive lipids include the eicosanoids (including thecannabinoids, leukotrienes, prostaglandins, lipoxins,epoxyeicosatrienoic acids, and isoeicosanoids), non-eicosanoidcannabinoid mediators, phospholipids and their derivatives such asphosphatidic acid (PA) and phosphatidylglycerol (PG), plateletactivating factor (PAF) and cardiolipins as well as lysophospholipidssuch as lysophosphatidyl choline (LPC) and various lysophosphatidicacids (LPA). Bioactive signaling lipid mediators also include thesphingolipids such as sphingomyelin, ceramide, ceramide-1-phosphate,sphingosine, sphingosylphosphoryl choline, sphinganine,sphinganine-1-phosphate (Dihydro-S1P) and sphingosine-1-phosphate.Sphingolipids and their derivatives represent a group of extracellularand intracellular signaling molecules with pleiotropic effects onimportant cellular processes. Other examples of bioactive signalinglipids include phosphatidylserine (PS), phosphatidylinositol (PI),phosphatidylethanolamine (PEA), diacylglyceride (DG), sulfatides,gangliosides, and cerebrosides.

Sphingolipids are a unique class of lipids that were named, due to theirinitially mysterious nature, after the Sphinx. Sphingolipids wereinitially characterized as primary structural components of cellmembranes, but recent studies indicate that sphingolipids also serve ascellular signaling and regulatory molecules (Hannun, et al., Adv. LipidRes. 25:27-41, 1993; Speigel, et al., FASEB J. 10:1388-1397, 1996;Igarashi, J. Biochem 122:1080-1087, 1997; Hla, T. (2004). Semin Cell DevBiol, 15, 513-2; Gardell, S. E., Dubin, A. E. & Chun, J. (2006). TrendsMol Med, 12, 65-75). Sphingolipids are primary structural components ofcell membranes that also serve as cellular signaling and regulatorymolecules (Hannun and Bell, Adv. Lipid Res. 25: 27-41, 1993; Igarashi,J. Biochem 122: 1080-1087, 1997). The sphingolipid signaling mediators,ceramide (CER), sphingosine (SPH) and sphingosine-1-phosphate (S1P),have been most widely studied and have recently been appreciated fortheir roles in the cardiovascular system, angiogenesis and tumor biology(Claus, et al., Curr Drug Targets 1: 185-205, 2000; Levade, et al.,Circ. Res. 89: 957-968, 2001; Wang, et al., J. Biol. Chem. 274:35343-50, 1999; Wascholowski and Giannis, Drug News Perspect. 14:581-90, 2001; Spiegel, S. & Milstien, S. (2003).Sphingosine-1-phosphate: an enigmatic signaling lipid. Nat Rev Mol CellBiol, 4, 397-407).

For a review of sphingolipid metabolism, see Liu, et al., Crit Rev.Clin. Lab. Sci. 36:511-573, 1999. For reviews of the sphingomyelinsignaling pathway, see Hannun, et al., Adv. Lipid Res. 25:27-41, 1993;Liu, et al., Crit. Rev. Clin. Lab. Sci. 36:511-573, 1999; Igarashi, J.Biochem. 122:1080-1087, 1997; Oral, et al., J. Biol. Chem.272:4836-4842, 1997; and Spiegel et al., Biochemistry (Moscow) 63:69-83,1998.

S1P is a mediator of cell proliferation and protects from apoptosisthrough the activation of survival pathways (Maceyka, et al. (2002),BBA, vol. 1585): 192-201, and Spiegel, et al. (2003), Nature ReviewsMolecular Cell Biology, vol. 4: 397-407). It has been proposed that thebalance between CER/SPH levels and S1P provides a rheostat mechanismthat decides whether a cell is directed into the death pathway or isprotected from apoptosis. The key regulatory enzyme of the rheostatmechanism is sphingosine kinase (SPHK) whose role is to convert thedeath-promoting bioactive signaling lipids (CER/SPH) into thegrowth-promoting S1P. S1P has two fates: S1P can be degraded by S1Plyase, an enzyme that cleaves S1P to phosphoethanolamine andhexadecanal, or, less common, hydrolyzed by S1P phosphatase to SPH.

The pleiotropic biological activities of S1P are mediated via a familyof G protein-coupled receptors (GPCRs) originally known as EndothelialDifferentiation Genes (EDG). Five GPCRs have been identified ashigh-affinity S1P receptors (S1PRs): S1P₁/EDG-1, S1P₂/EDG-5, S1P₃/EDG-3,S1P₄/EDG-6, and S1P₅/EDG-8 only identified as late as 1998 (Lee, et al.,1998). Many responses evoked by S1P are coupled to differentheterotrimeric G proteins (G_(q−), G_(i), G₁₂₋₁₃) and the small GTPasesof the Rho family (Gardell, et al., 2006).

In the adult, S1P is released from platelets (Murata et al., 2000) andmast cells to create a local pulse of free S1P (sufficient enough toexceed the Kd of the S1PRs) for promoting wound healing andparticipating in the inflammatory response. Under normal conditions, thetotal S1P in the plasma is quite high (300-500 nM); however, it has beenhypothesized that most of the S1P may be ‘buffered’ by serum proteins,particularly lipoproteins (e.g., HDL>LDL>VLDL) and albumin, so that thebio-available S1P (or the free fraction of S1P) is not sufficient toappreciably activate S1PRs (Murata et al., 2000). If this were not thecase, inappropriate angiogenesis and inflammation would result.Intracellular actions of S1P have also been suggested (see, e.g.,Spiegel S, Kolesnick R (2002), Leukemia, vol. 16: 1596-602; Suomalainen,et al (2005), Am J Pathol, vol. 166: 773-81).

Widespread expression of the cell surface S1P receptors allows S1P toinfluence a diverse spectrum of cellular responses, includingproliferation, adhesion, contraction, motility, morphogenesis,differentiation, and survival. This spectrum of response appears todepend upon the overlapping or distinct expression patterns of the S1Preceptors within the cell and tissue systems. In addition, crosstalkbetween S1P and growth factor signaling pathways, includingplatelet-derived growth factor (PDGF), vascular endothelial growthfactor (VEGF), and basic fibroblastic growth factor (bFGF), haverecently been demonstrated (see, e.g., Baudhuin, et al. (2004), FASEB J,vol. 18: 341-3). The regulation of various cellular processes involvingS1P has particular impact on neuronal signaling, vascular tone, woundhealing, immune cell trafficking, reproduction, and cardiovascularfunction, among others. Alterations of endogenous levels of S1P withinthese systems can have detrimental effects, eliciting severalpathophysiological conditions, including cancer, inflammation,angiogenesis, heart disease, asthma, and autoimmune diseases.

A recent novel approach to the treatment of various diseases anddisorders, including cardiovascular diseases, cerebrovascular diseases,and various cancers, involves reducing levels of biologically availableS1P, either alone or in combination with other treatments. Whilesphingolipid-based treatment strategies that target key enzymes of thesphingolipid metabolic pathway, such as SPHK, have been proposed,interference with the lipid mediator S1P itself has not until recentlybeen emphasized, largely because of difficulties in directly mitigatingthis lipid target, in particular because of the difficulty first inraising and then in detecting antibodies against the S1P target.

Recently, the generation of antibodies specific for S1P has beendescribed. See, e.g., commonly owned, U.S. patent application Serial No.20070148168; WO2007/053447. Such antibodies, which can, for example,selectively adsorb S1P from serum, act as molecular sponges toneutralize extracellular S1P. See also commonly owned U.S. Pat. Nos.6,881,546 and 6,858,383 and U.S. patent application Ser. No. 10/029,372.SPHINGOMAB™, the murine monoclonal antibody (mAb) developed by Lpath,Inc. and described in certain patents or patent applications listedabove, has been shown to be effective in models of human disease. Insome situations, a humanized antibody may be preferable to a murineantibody, particularly for therapeutic uses in humans, wherehuman-anti-mouse antibody (HAMA) response may occur. Such a response mayreduce the effectiveness of the antibody by neutralizing the bindingactivity and/or by rapidly clearing the antibody from circulation in thebody. The HAMA response can also cause toxicities with subsequentadministrations of mouse antibodies.

A humanized anti-S1P antibody has now been developed and is describedherein. This antibody is expected to have all the advantages of themurine mAb in terms of efficacy in binding S1P, neutralizing S1P andmodulating disease states related to S1P, but with none of the potentialdisadvantages of the murine mAb when used in a human context. Asdescribed in the examples hereinbelow, this humanized antibody (referredto as LT1009 or sonepcizumab) has in fact shown activity greater thanthat of the parent (murine) antibody in animal models of disease.

3. Definitions

Before describing the instant invention in detail, several terms used inthe context of the present invention will be defined. In addition tothese terms, others are defined elsewhere in the specification, asnecessary. Unless otherwise expressly defined herein, terms of art usedin this specification will have their art-recognized meanings. In theevent of conflict, the present specification, including definitions,will control.

An “immune-derived moiety” includes any antibody (Ab) or immunoglobulin(Ig), and refers to any form of a peptide, polypeptide derived from,modeled after or encoded by, an immunoglobulin gene, or a fragment ofsuch peptide or polypeptide that is capable of binding an antigen orepitope (see, e.g., Immunobiology, 5th Edition, Janeway, Travers,Walport, Shlomchiked. (editors), Garland Publishing (2001)). In thepresent invention, the antigen is a bioactive lipid molecule.

An “anti-S1P antibody” or an “immune-derived moiety reactive againstS1P” refers to any antibody or antibody-derived molecule that binds S1P.As will be understood from these definitions, antibodies orimmune-derived moieties may be polyclonal or monoclonal and may begenerated through a variety of means, and/or may be isolated from ananimal, including a human subject.

A “bioactive lipid” refers to a lipid signaling molecule. In general, abioactive lipid does not reside in a biological membrane when it exertsits signaling effects, which is to say that while such a lipid speciesmay exist at some point in a biological membrane (for example, a cellmembrane, a membrane of a cell organelle, etc.), when associated with abiological membrane it is not a “bioactive lipid” but is instead a“structural lipid” molecule. Bioactive lipids are distinguished fromstructural lipids (e.g., membrane-bound phospholipids) in that theymediate extracellular and/or intracellular signaling and thus areinvolved in controlling the function of many types of cells bymodulating differentiation, migration, proliferation, secretion,survival, and other processes. In vivo, bioactive lipids can be found inextracellular fluids, where they can be complexed with other molecules,for example serum proteins such as albumin and lipoproteins, or in“free” form, i.e., not complexed with another molecule species. Asextracellular mediators, some bioactive lipids alter cell signaling byactivating membrane-bound ion channels or G-protein coupled receptorsthat, in turn, activate complex signaling systems that result in changesin cell function or survival. As intracellular mediators, bioactivelipids can exert their actions by directly interacting withintracellular components such as enzymes and ion channels.Representative examples of bioactive lipids include LPA and S1P.

The term “therapeutic agent” means an agent to mitigate angiogenesisand/or neovascularization, e.g., CNV and BV maturation, edema, vascularpermeability and fibrosis, fibrogenesis and scarring associated with, orpart of the underlying pathology of, ocular diseases and conditions.

The term “combination therapy” refers to a therapeutic regimen thatinvolves the provision of at least two distinct therapies to achieve anindicated therapeutic effect. For example, a combination therapy mayinvolve the administration of two or more chemically distinct activeingredients, for example, an anti-LPA antibody and an anti-S1P antibody.Alternatively, a combination therapy may involve the administration ofan immune-derived moiety reactive against a bioactive lipid and theadministration of one or more other chemotherapeutic agents. Combinationtherapy may, alternatively, involve administration of an anti-lipidantibody together with the delivery of another treatment, such asradiation therapy and/or surgery. Further, a combination therapy mayinvolve administration of an anti-lipid antibody together with one ormore other biological agents (e.g., anti-VEGF, TGFβ, PDGF, or bFGFagent), chemotherapeutic agents and another treatment such as radiationand/or surgery. In the context of combination therapy using two or morechemically distinct active ingredients, it is understood that the activeingredients may be administered as part of the same composition or asdifferent compositions. When administered as separate compositions, thecompositions comprising the different active ingredients may beadministered at the same or different times, by the same or differentroutes, using the same of different dosing regimens, all as theparticular context requires and as determined by the attendingphysician. Similarly, when one or more anti-lipid antibody species, forexample, an anti-LPA antibody, alone or in conjunction with one or morechemotherapeutic agents are combined with, for example, radiation and/orsurgery, the drug(s) may be delivered before or after surgery orradiation treatment.

An “anti-S1P agent” refers to any agent that is specifically reactive toS1P, and includes antibodies or antibody-derived molecules ornon-antibody-derived moieties that bind S1P and its variants.

A “hapten” refers to a molecule adapted for conjugation to a hapten,thereby rendering the hapten immunogenic. A representative, non-limitingclass of hapten molecules is proteins, examples of which includealbumin, keyhole limpet hemocyanin, hemaglutanin, tetanus, anddiphtheria toxoid. Other classes and examples of hapten moleculessuitable for use in accordance with the invention are known in the art.These, as well as later discovered or invented naturally occurring orsynthetic haptens, can be adapted for application in accordance with theinvention.

The term “chemotherapeutic agent” means anti-cancer and otheranti-hyperproliferative agents. Put simply, a “chemotherapeutic agent”refers to a chemical intended to destroy cells and tissues. Such agentsinclude, but are not limited to: (1) DNA damaging agents and agents thatinhibit DNA synthesis: e.g., anthracyclines (e.g., doxorubicin,donorubicin, epirubicin), alkylating agents (e.g., bendamustine,busulfan, carboplatin, carmustine, cisplatin, chlorambucil,cyclophosphamide, dacarbazine, hexamethylmelamine, ifosphamide,lomustine, mechlorethamine, melphalan, mitotane, mytomycin, pipobroman,procarbazine, streptozocin, thiotepa, and triethylenemelamine), platinumderivatives (e.g., cisplatin, carboplatin, cisdiamminedichloroplatinum), telomerase and topoisomerase inhibitors(e.g., Camptosar), (2) tubulin-depolymerizing agents: e.g., taxoids(e.g., Paclitaxel, docetaxel, BAY 59-8862), (3) anti-metabolites such ascapecitabine, chlorodeoxyadenosine, cytarabine (and its activated form,ara-CMP), cytosine arabinoside, dacabazine, floxuridine, fludarabine,5-fluorouracil, 5-DFUR, gemcitibine, hydroxyurea, 6-mercaptopurine,methotrexate, pentostatin, trimetrexate, and 6-thioguanine (4)anti-angiogenics (e.g., Avastin, thalidomide, revlimid, sunitinib,lenalidomide), vascular disrupting agents (e.g., flavonoids/flavones,DMXAA, combretastatin derivatives such as CA4DP, ZD6126, AVE8062A,etc.), (5) biologics such as antibodies or antibody fragments (e.g.,Herceptin, Avastin, Panorex, Rituxan, Zevalin, Mylotarg, Campath, Bexar,Erbitux, Lucentis), and (6) endocrine therapy: e.g., aromataseinhibitors (e.g., 4-hydroandrostendione, exemestane, aminoglutehimide,anastrozole, letozole), anti-estrogens (e.g., Tamoxifen, Toremifine,Raoxifene, Faslodex), steroids such as dexamethasone, (7)immuno-modulators: e.g., cytokines such as IFN-beta and IL2), inhibitorsto integrins, other adhesion proteins and matrix metalloproteinases),(8) histone deacetylase inhibitors, (9) inhibitors of signaltransduction such as inhibitors of tyrosine kinases like imatinib(Gleevec), (10) inhibitors of heat shock proteins, (11) retinoids suchas all trans retinoic acid, (12) inhibitors of growth factor receptorsor the growth factors themselves, (13) anti-mitotic compounds such asnavelbine, Paclitaxel, taxotere, vinblastine, vincristine, vindesine,and vinorelbine, (14) anti-inflammatories such as COX inhibitors and(15) cell cycle regulators, e.g., check point regulators and telomeraseinhibitors.

The term “sphingolipid” as used herein refers to the class of compoundsin the art known as sphingolipids, including, but not limited to thefollowing compounds (see http//www.lipidmaps.org as the site containingthe links indicated by the bracketed alphanumeric strings below, whichlinks contain chemical formulas, structural information, etc. for thecorresponding compounds):

-   Sphingoid bases [SPO1]

Sphing-4-enines (Sphingosines) [SP0101]

Sphinganines [SP0102]

4-Hydroxysphinganines (Phytosphingosines) [SP0103]

Sphingoid base homologs and variants [SP0104]

Sphingoid base 1-phosphates [SP0105]

Lysosphingomyelins and lysoglycosphingolipids [SP0106]

N-methylated sphingoid bases [SP0107]

Sphingoid base analogs [SP0108]

-   Ceramides [SP02]

N-acylsphingosines (ceramides) [SP0201]

N-acylsphinganines (dihydroceramides) [SP0202]

N-acyl-4-hydroxysphinganines (phytoceramides) [SP0203]

Acylceramides [SP0204]

Ceramide 1-phosphates [SP0205]

-   Phosphosphingolipids [SP03]

Ceramide phosphocholines (sphingomyelins) [SP0301]

Ceramide phosphoethanolamines [SP0302]

Ceramide phosphoinositols [SP0303]

-   Phosphonosphingolipids [SP04]-   Neutral glycosphingolipids [SP05]

Simple Glc series (GlcCer, LacCer, etc) [SP0501]

GalNAcb1-3Gala1-4Galb1-4Glc- (Globo series) [SP0502]

GalNAcb1-4Galb1-4Glc- (Ganglio series) [SP0503]

Galb1-3GlcNAcb1-3Galb1-4Glc- (Lacto series) [SP0504]

Galb1-4GlcNAcb1-3Galb1-4Glc- (Neolacto series) [SP0505]

GalNAcb1-3Gala1-3Galb1-4Glc- (Isoglobo series) [SP0506]

GlcNAcb1-2Mana1-3Manb1-4Glc- (Mollu series) [SP0507]

GalNAcb1-4GlcNAcb1-3Manb1-4Glc- (Arthro series) [SP0508]

Gal- (Gala series) [SP0509]

Other [SP0510]

-   Acidic glycosphingolipids [SP06]

Gangliosides [SP0601]

Sulfoglycosphingolipids (sulfatides) [SP0602]

Glucuronosphingolipids [SP0603]

Phosphoglycosphingolipids [SP0604]

Other [SP0600]

-   Basic glycosphingolipids [SP07]-   Amphoteric glycosphingolipids [SP08]-   Arsenosphingolipids [SP09]

The present invention provides anti-sphingolipid S1P agents that areuseful for treating or preventing hyperproliferative disorders such ascancer and cardiovascular or cerebrovascular diseases and disorders andvarious ocular disorders, as described in greater detail below. Inparticular the invention is drawn to S1P and its variants including butare not limited to sphingosine-1-phosphate [sphingene-1-phosphate;D-erythro-sphingosine-1-phosphate; sphing-4-enine-1-phosphate;(E,2S,3R)-2-amino-3-hydroxy-octadec-4-enoxy]phosphonic acid (AS26993-30-6), DHS1P is defined asdihydrosphingosine-1-phosphate[sphinganine-1-phosphate;[(2S,3R)-2-amino-3-hydroxy-octadecoxy]phosphonic acid;D-Erythro-dihydro-D-sphingosine-1-phosphate (CAS 19794-97-9]; SPC issphingosylphosphoryl choline, lysosphingomyelin,sphingosylphosphocholine, sphingosine phosphorylcholine, ethanaminium;2-((((2-amino-3-hydroxy-4-octadecenyl)oxy)hydroxyphosphinyl)oxy)-N,N,N-trimethyl-,chloride, (R-(R*,S*-(E))),2-[[(E,2R,3S)-2-amino-3-hydroxy-octadec-4-enoxy]-hydroxy-phosphoryl]oxyethy1-trimethyl-azanium chloride (CAS 10216-23-6).

The term “epitope” or “antigenic determinant” when used herein, unlessindicated otherwise, refers to the region of S1P to which an anti-S1Pagent is reactive to.

The term “hyperproliferative disorder” refers to diseases and disordersassociated with, the uncontrolled proliferation cells, including but notlimited to uncontrolled growth of organ and tissue cells resulting incancers or neoplasia and benign tumors. Hyperproliferative disordersassociated with endothelial cells can result in diseases of angiogenesissuch as angiomas, endometriosis, obesity, age-related maculardegeneration and various retinopathies, as well as the proliferation ofendothelial cells and smooth muscle cells that cause restenosis as aconsequence of stenting in the treatment of atherosclerosis.Hyperproliferative disorders involving fibroblasts (for example,fibrogenesis) include but are not limited to disorders of excessivescarring (for example, fibrosis) such as age-related maculardegeneration, cardiac remodeling and failure associated with myocardialinfarction, excessive wound healing such as commonly occurs as aconsequence of surgery or injury, keloids, and fibroid tumors andstenting.

The compositions of the invention are used in methods ofsphingolipid-based therapy. “Therapy” refers to the prevention and/ortreatment of diseases, disorders or physical trauma.

“Cardiovascular therapy” encompasses cardiac therapy as well as theprevention and/or treatment of other diseases associated with thecardiovascular system, such as heart disease. The term “heart disease”encompasses any type of disease, disorder, trauma or surgical treatmentthat involves the heart or myocardial tissue. Of particular interest areheart diseases that relate to hypoxia and/or ischemia of myocardialtissue and/or heart failure. One type of heart disease that can resultfrom ischemia is reperfusion injury, such as can occur whenanti-coagulants, thrombolytic agents, or anti-anginal medications areused in therapy, or when the cardiac vasculature is surgically opened byangioplasty or by coronary artery grafting. Another type of heartdisease to which the invention is directed is coronary artery disease(CAD), which can arise from arteriosclerosis, particularlyatherosclerosis, a common cause of ischemia. CAD has symptoms such asstable or unstable angina pectoris, and can lead to myocardialinfarctions (MI) and sudden cardiac death. Conditions of particularinterest include, but are not limited to, myocardial ischemia; acutemyocardial infarction (AMI); coronary artery disease (CAD); acutecoronary syndrome (ACS); cardiac cell and tissue damage that may occurduring or as a consequence of pericutaneous revascularization (coronaryangioplasty) with or without stenting; coronary bypass grafting (CABG)or other surgical or medical procedures or therapies that may causeischemic or ischemic/reperfusion damage in humans; and cardiovasculartrauma. The term “heart failure” encompasses acute myocardialinfarction, myocarditis, a cardiomyopathy, congestive heart failure,septic shock, cardiac trauma and idiopathic heart failure. The spectrumof ischemic conditions that result in heart failure is referred to asAcute Coronary Syndrome (ACS).

The term “cardiotherapeutic agent” refers to an agent that istherapeutic to diseases and diseases caused by or associated withcardiac and myocardial diseases and disorders.

“Cerebrovascular therapy” refers to therapy directed to the preventionand/or treatment of diseases and disorders associated with cerebralischemia and/or hypoxia. Of particular interest is cerebral ischemiaand/or hypoxia resulting from global ischemia resulting from a heartdisease, including without limitation heart failure.

The term “sphingolipid metabolite” refers to a compound from which asphingolipid is made, as well as a that results from the degradation ofa particular sphingolipid. In other words, a “sphingolipid metabolite”is a compound that is involved in the sphingolipid metabolic pathways.Metabolites include metabolic precursors and metabolic products. Theterm “metabolic precursors” refers to compounds from which sphingolipidsare made. Metabolic precursors of particular interest include but arenot limited to SPC, sphingomyelin, dihydrosphingosine, dihydroceramide,and 3-ketosphinganine. The term “metabolic products” refers to compoundsthat result from the degradation of sphingolipids, such asphosphorylcholine (e.g., phosphocholine, choline phosphate), fattyacids, including free fatty acids, and hexadecanal (e.g.,palmitaldehyde).

As used herein, the term “therapeutic” encompasses the fill spectrum oftreatments for a disease or disorder. A “therapeutic” agent of theinvention may act in a manner that is prophylactic or preventive,including those that incorporate procedures designed to targetindividuals that can be identified as being at risk (pharmacogenetics);or in a manner that is ameliorative or curative in nature; or may act toslow the rate or extent of the progression of at least one symptom of adisease or disorder being treated; or may act to minimize the timerequired, the occurrence or extent of any discomfort or pain, orphysical limitations associated with recuperation from a disease,disorder or physical trauma; or may be used as an adjuvant to othertherapies and treatments.

“Treatment” refers to both therapeutic treatment and prophylactic orpreventative measures. Those in need of treatment include those alreadywith the disorder as well as those in which the disorder is to beprevented.

The term “combination therapy” refers to a therapeutic regimen thatinvolves the provision of at least two distinct therapies to achieve anindicated therapeutic effect. For example, a combination therapy mayinvolve the administration of two or more chemically distinct activeingredients, for example, a fast-acting chemotherapeutic agent and ananti-lipid antibody. Alternatively, a combination therapy may involvethe administration of an anti-lipid antibody and/or one or morechemotherapeutic agents, alone or together with the delivery of anothertreatment, such as radiation therapy and/or surgery. Further, acombination therapy may involve administration of an anti-lipid antibodytogether with one or more other biological agents (e.g., anti-VEGF,TGFβ, PDGF, or bFGF agent), chemotherapeutic agents and anothertreatment such as radiation and/or surgery. In the context of theadministration of two or more chemically distinct active ingredients, itis understood that the active ingredients may be administered as part ofthe same composition or as different compositions. When administered asseparate compositions, the compositions comprising the different activeingredients may be administered at the same or different times, by thesame or different routes, using the same of different dosing regimens,all as the particular context requires and as determined by theattending physician. Similarly, when one or more anti-lipid antibodyspecies, for example, an anti-LPA antibody, alone or in conjunction withone or more chemotherapeutic agents are combined with, for example,radiation and/or surgery, the drug(s) may be delivered before or aftersurgery or radiation treatment.

“Monotherapy” refers to a treatment regimen based on the delivery of onetherapeutically effective compound, whether administered as a singledose or several doses over time.

“Neoplasia” or “cancer” refers to abnormal and uncontrolled cell growth.A “neoplasm”, or tumor or cancer, is an abnormal, unregulated, anddisorganized proliferation of cell growth, and is generally referred toas cancer. A neoplasm may be benign or malignant. A neoplasm ismalignant, or cancerous, if it has properties of destructive growth,invasiveness, and metastasis. Invasiveness refers to the local spread ofa neoplasm by infiltration or destruction of surrounding tissue,typically breaking through the basal laminas that define the boundariesof the tissues, thereby often entering the body's circulatory system.Metastasis typically refers to the dissemination of tumor cells bylymphatics or blood vessels. Metastasis also refers to the migration oftumor cells by direct extension through serous cavities, or subarachnoidor other spaces. Through the process of metastasis, tumor cell migrationto other areas of the body establishes neoplasms in areas away from thesite of initial appearance.

“Mammal” for purposes of treatment refers to any animal classified as amammal, including humans, domestic and farm animals, and zoo, sports, orpet animals, such as dogs, horses, cats, cows, etc. Preferably, themammal is human.

“Native antibodies” and “native immunoglobulins” are usuallyheterotetrameric glycoproteins of about 150,000 Daltons, composed of twoidentical light (L) chains and two identical heavy (H) chains. Eachlight chain is linked to a heavy chain by one covalent disulfide bond,while the number of disulfide linkages varies among the heavy chains ofdifferent immunoglobulin isotypes. Each heavy and light chain also hasregularly spaced intrachain disulfide bridges. Each heavy chain has atone end a variable domain (V_(H)) followed by a number of constantdomains. Each light chain has a variable domain at one end (V_(L)) and aconstant domain at its other end; the constant domain of the light chainis aligned with the first constant domain of the heavy chain, and thelight-chain variable domain is aligned with the variable domain of theheavy chain. Particular amino acid residues are believed to form aninterface between the light- and heavy-chain variable domains.

The term “variable” region comprises framework and CDRs (otherwise knownas hypervariables) and refers to the fact that certain portions of thevariable domains differ extensively in sequence among antibodies and areused in the binding and specificity of each particular antibody for itsparticular antigen. However, the variability is not evenly distributedthroughout the variable domains of antibodies. It is concentrated inthree segments called hypervariable regions both in the light chain andthe heavy chain variable domains. The more highly conserved portions ofvariable domains are called the framework region (FR). The variabledomains of native heavy and light chains each comprise four FRs (FR1,FR2, FR3 and FR4, respectively), largely adopting a β-sheetconfiguration, connected by three hypervariable regions, which formloops connecting, and in some cases forming part of, the β-sheetstructure. The hypervariable regions in each chain are held together inclose proximity by the FRs and, with the hypervariable regions from theother chain, contribute to the formation of the antigen-binding site ofantibodies (see Kabat, et al., Sequences of Proteins of ImmunologicalInterest, 5th Ed. Public Health Service, National Institutes of Health,Bethesda, Md. (1991), pages 647-669). The constant domains are notinvolved directly in binding an antibody to an antigen, but exhibitvarious effector functions, such as participation of the antibody inantibody-dependent cellular toxicity.

The term “hypervariable region” when used herein refers to the aminoacid residues of an antibody which are responsible for antigen binding.The hypervariable region comprises amino acid residues from a“complementarity determining region” or “CDR” (for example, residues24-34 (L1), 50-56 (L2), and 89-97 (L3) in the light chain variabledomain and 31-35 (H1), 50-65 (H2), and 95-102 (H3) in the heavy chainvariable domain; Kabat, et al. (1991), above) and/or those residues froma “hypervariable loop” (for example residues 26-32 (L1), 50-52 (L2), and91-96 (L3) in the light chain variable domain and 26-32 (H1), 53-55(H2), and 96-101 (H3) in the heavy chain variable domain; Chothia andLesk J. Mol. Biol. 196:901-917 (1987)). “Framework” or “FR’ residues arethose variable domain residues other than the hypervariable regionresidues as herein defined.

Papain digestion of antibodies produces two identical antigen-bindingfragments, called “Fab” fragments, each with a single antigen-bindingsite, and a residual “Fc” fragment, whose name reflects its ability tocrystallize readily. Pepsin treatment yields an F(ab′)₂ fragment thathas two antigen-combining sites and is still capable of cross-linkingantigen.

“Fv” is the minimum antibody fragment that contains a completeantigen-recognition and -binding site. This region consists of a dimerof one heavy chain and one light chain variable domain in tight,non-covalent association. It is in this configuration that the threehypervariable regions of each variable domain interact to define anantigen-binding site on the surface of the V_(H)-V_(L) dimer.Collectively, the six hypervariable regions confer antigen-bindingspecificity to the antibody. However, even a single variable domain (orhalf of an Fv comprising only three hypervariable regions specific foran antigen) has the ability to recognize and bind antigen, although at alower affinity than the entire binding site.

The Fab fragment also contains the constant domain of the light chainand the first constant domain (CH1) of the heavy chain. Fab′ fragmentsdiffer from Fab fragments by the addition of a few residues at thecarboxyl terminus of the heavy chain CH1 domain including one or morecysteine(s) from the antibody hinge region. Fab′-SH is the designationherein for Fab′ in which the cysteine residue(s) of the constant domainsbear a free thiol group. F(ab′)₂ antibody fragments originally wereproduced as pairs of Fab′ fragments which have hinge cysteines betweenthem. Other chemical couplings of antibody fragments are also known.

The “light chains” of antibodies (immunoglobulins) from any vertebratespecies can be assigned to one of two clearly distinct types, calledkappa (κ) and lambda (λ), based on the amino acid sequences of theirconstant domains.

Depending on the amino acid sequence of the constant domain of theirheavy chains, immunoglobulins can be assigned to different classes.Presently there are five major classes of immunoglobulins: IgA, IgD,IgE, IgG, and IgM, and several of these may be further divided intosubclasses (isotypes), e.g., IgG1, IgG2, IgG3, IgG4, IgA, and IgA2. Theheavy-chain constant domains that correspond to the different classes ofimmunoglobulins are called alpha, delta, epsilon, gamma, and mu,respectively. The subunit structures and three-dimensionalconfigurations of different classes of immunoglobulins are well known.

The term “antibody” herein is used in the broadest sense andspecifically covers monoclonal antibodies (including full lengthmonoclonal antibodies), polyclonal antibodies, multispecific antibodies(e.g., bispecific antibodies), antibody fragments, and binding agentsthat employ the CDRs (or variant thereof that retain antigen bindingactivity) of the parent antibody. Antibodies are defined herein asretaining at least one desired activity of the parent antibody. Desiredactivities can include the ability to bind the antigen specifically, theability to inhibit proleration in vitro, the ability to inhibitangiogenesis in vivo, and the ability to alter cytokine profile invitro. “Antibody fragments” comprise a portion of a full-lengthantibody, generally the antigen binding or variable domain thereof.Examples of antibody fragments include Fab, Fab′, F(ab′)₂, and Fvfragments; diabodies; linear antibodies; single-chain antibodymolecules; and multispecific antibodies formed from antibody fragments.

The term “monoclonal antibody” as used herein refers to an antibodyobtained from a population of substantially homogeneous antibodies, forexample, the individual antibodies comprising the population areidentical except for possible naturally occurring mutations that may bepresent in minor amounts. Monoclonal antibodies are highly specific,being directed against a single antigenic site. Furthermore, in contrastto conventional (polyclonal) antibody preparations that typicallyinclude different antibodies directed against different determinants(epitopes), each monoclonal antibody is directed against a singledeterminant on the antigen. The modifier “monoclonal” indicates thecharacter of the antibody as being obtained from a substantiallyhomogeneous population of antibodies, and is not to be construed asrequiring production of the antibody by any particular method. Forexample, the monoclonal antibodies to be used in accordance with thepresent invention may be made by the hybridoma method first described byKohler, et al., Nature 256:495 (1975), or may be made by recombinant DNAmethods (see, e.g., U.S. Pat. No. 4,816,567). The “monoclonalantibodies” may also be isolated from phage antibody libraries using thetechniques described in Clackson, et al., Nature 352:624-628 (1991) andMarks et al., J. Mol. Biol. 222:581-597 (1991), for example.

The monoclonal antibodies herein specifically include “chimeric”antibodies (immunoglobulins) in which a portion of the heavy and/orlight chain is identical with or homologous to corresponding sequencesin antibodies derived from a particular species or belonging to aparticular antibody class or subclass, while the remainder of thechain(s) is identical with or homologous to corresponding sequences inantibodies derived from another species or belonging to another antibodyclass or subclass, as well as fragments of such antibodies, so long asthey exhibit the desired biological activity (U.S. Pat. No. 4,816,567;and Morrison, et al., Proc. Natl. Acad. Sci. USA 81:6851-6855 (1984)).

“Humanized” forms of non-human (e.g., murine) antibodies are chimericantibodies that contain minimal sequence derived from non-humanimmunoglobulin. For the most part, humanized antibodies are humanimmunoglobulins (recipient antibody) in which hypervariable regionresidues of the recipient are replaced by hypervariable region residuesfrom a non-human species (donor antibody) such as mouse, rat, rabbit ornonhuman primate having the desired specificity, affinity, and capacity.In some instances, framework region (FR) residues of the humanimmunoglobulin are replaced by corresponding non-human residues.Furthermore, humanized antibodies may comprise residues that are notfound in the recipient antibody or in the donor antibody. Thesemodifications are made to further refine antibody performance. Ingeneral, the humanized antibody will comprise substantially all of atleast one, and typically two, variable domains, in which all orsubstantially all of the hypervariable regions correspond to those of anon-human immunoglobulin and all or substantially all of the FRs arethose of a human immunoglobulin sequence. The humanized antibodyoptionally also will comprise at least a portion of an immunoglobulinconstant region (Fc), typically that of a human immunoglobulin. Forfurther details, see Jones, et al., Nature 321:522-525 (1986);Reichmann, et al., Nature 332:323-329 (1988); and Presta, Curr. Op.Struct. Biol. 2:593-596 (1992) and Hansen, WO2006105062.

“Single-chain Fv” or “sFv” antibody fragments comprise the V_(H) andV_(L) domains of antibody, wherein these domains are present in a singlepolypeptide chain. Generally, the Fv polypeptide further comprises apolypeptide linker between the V_(H) and V_(L) domains that enables thesFv to form the desired structure for antigen binding. For a review ofsFv, see Pluckthun in The Pharmacology of Monoclonal Antibodies, vol.113, Rosenburg and Moore eds. Springer-Verlag, New York, pp. 269-315(1994).

The term “diabodies” refers to small antibody fragments with twoantigen-binding sites, which fragments comprise a heavy chain variabledomain (V_(H)) connected to a light chain variable domain (V_(L)) in thesame polypeptide chain (V_(H)-V_(L)). By using a linker that is tooshort to allow pairing between the two domains on the same chain, thedomains are forced to pair with the complementary domains of anotherchain and create two antigen-binding sites. Diabodies are described morefully in, for example, EP 404,097; WO 93/11161; and Hollinger, et al.,Proc. Natl. Acad. Sci. USA 90:6444-6448 (1993).

The expression “linear antibodies” when used throughout this applicationrefers to the antibodies described in Zapata, et al. Protein Eng.8(10):1057-1062 (1995). Briefly, these antibodies comprise a pair oftandem Fd segments (V_(H)-C_(H)1-V_(H)-C_(H)1) that form a pair ofantigen binding regions. Linear antibodies can be bispecific ormonospecific.

A “variant” anti-sphingolipid antibody, refers herein to a moleculewhich differs in amino acid sequence from a “parent” anti-sphingolipidantibody amino acid sequence by virtue of addition, deletion, and/orsubstitution of one or more amino acid residue(s) in the parent antibodysequence and retains at least one desired activity of the parentanti-binding antibody. Desired activities can include the ability tobind the antigen specifically, the ability to inhibit proleration invitro, the ability to inhibit angiogenesis in vivo, and the ability toalter cytokine profile in vitro. In one embodiment, the variantcomprises one or more amino acid substitution(s) in one or morehypervariable region(s) of the parent antibody. For example, the variantmay comprise at least one, e.g. from about one to about ten, andpreferably from about two to about five, substitutions in one or morehypervariable regions of the parent antibody. Ordinarily, the variantwill have an amino acid sequence having at least 50% amino acid sequenceidentity with the parent antibody heavy or light chain variable domainsequences, more preferably at least 65%, more preferably at least 75%,more preferably at least 80%, more preferably at least 85%, morepreferably at least 90%, and most preferably at least 95% sequenceidentity. Identity or homology with respect to this sequence is definedherein as the percentage of amino acid residues in the candidatesequence that are identical with the parent antibody residues, afteraligning the sequences and introducing gaps, if necessary, to achievethe maximum percent sequence identity. None of N-terminal, C-terminal,or internal extensions, deletions, or insertions into the antibodysequence shall be construed as affecting sequence identity or homology.The variant retains the ability to bind a sphingolipid and preferablyhas desired activities which are superior to those of the parentantibody. For example, the variant may have a stronger binding affinity,enhanced ability to reduce angiogenesis and/or halt tumor progression.To analyze such desired properties (for example less immunogenic, longerhalf-life, enhanced stability, enhanced potency), one should compare aFab form of the variant to a Fab form of the parent antibody or a fulllength form of the variant to a full length form of the parent antibody,for example, since it has been found that the format of theanti-sphingolipid antibody impacts its activity in the biologicalactivity assays disclosed herein. The variant antibody of particularinterest herein can be one which displays at least about 5%, preferablyat least about 10%, 25%, 59%, or more of at least one desired activity.The preferred variant is one that has superior biophysical properties asmeasured in vitro or superior activities biological as measured in vitroor in vivo when compared to the parent antibody.

The “parent” antibody herein is one that is encoded by an amino acidsequence used for the preparation of the variant. Preferably, the parentantibody has a human framework region and, if present, has humanantibody constant region(s). For example, the parent antibody may be ahumanized or human antibody.

An “isolated” antibody is one that has been identified and separatedand/or recovered from a component of its natural environment.Contaminant components of its natural environment are materials thatwould interfere with diagnostic or therapeutic uses for the antibody,and may include enzymes, hormones, and other proteinaceous ornonproteinaceous solutes. In preferred embodiments, the antibody will bepurified (1) to greater than 95% by weight of antibody as determined bythe Lowry method, and most preferably more than 99% by weight, (2) to adegree sufficient to obtain at least 15 residues of N-terminal orinternal amino acid sequence by use of a spinning cup sequenator, or (3)to homogeneity by SDS-PAGE under reducing or nonreducing conditionsusing Coomassie blue or, preferably, silver stain. Isolated antibodyincludes the antibody in situ within recombinant cells since at leastone component of the antibody's natural environment will not be present.Ordinarily, however, isolated antibody will be prepared by at least onepurification step.

The word “label” when used herein refers to a detectable compound orcomposition that is conjugated directly or indirectly to the antibody.The label may itself be detectable by itself (e.g., radioisotope labelsor fluorescent labels) or, in the case of an enzymatic label, maycatalyze chemical alteration of a substrate compound or composition thatis detectable.

By “solid phase” is meant a non-aqueous matrix to which the antibody ofthe present invention can adhere or upon which the antibody or otheranti-S1P binding reagent can otherwise become immoblized. Examples ofsolid phases encompassed herein include those formed partially orentirely of glass (e.g., controlled pore glass), polysaccharides (e.g.,agarose), polyacrylamides, polystyrene, polyvinyl alcohol and silicones.In certain embodiments, depending on the context, the solid phase cancomprise the well of an assay plate, while in others it is apurification column (e.g., an affinity chromatography column). This termalso includes a discontinuous solid phase of discrete particles, such asthose described in U.S. Pat. No. 4,275,149.

A “liposome” is a small vesicle composed of various types of lipids,phospholipids and/or surfactant that is useful for delivery of a drug(such as the anti-sphingolipid antibodies disclosed herein and,optionally, a chemotherapeutic agent) to a mammal. The components of theliposome are commonly arranged in a bilayer formation, similar to thelipid arrangement of biological membranes. An “isolated” nucleic acidmolecule is a nucleic acid molecule that is identified and separatedfrom at least one contaminant nucleic acid molecule with which it isordinarily associated in the natural source of the antibody nucleicacid. An isolated nucleic acid molecule is other than in the form orsetting in which it is found in nature. Isolated nucleic acid moleculestherefore are distinguished from the nucleic acid molecule as it existsin natural cells. However, an isolated nucleic acid molecule includes anucleic acid molecule contained in cells that ordinarily express theantibody where, for example, the nucleic acid molecule is in achromosomal location different from that of natural cells.

The expression “control sequences” refers to DNA sequences necessary forthe expression of an operably linked coding sequence in a particularhost organism. The control sequences that are suitable for prokaryotes,for example, include a promoter, optionally an operator sequence, and aribosome binding site. Eukaryotic cells are known to utilize promoters,polyadenylation signals, and enhancers.

Nucleic acid is “operably linked” when it is placed into a functionalrelationship with another nucleic acid sequence. For example, DNA for apresequence or secretory leader is operably linked to DNA for apolypeptide if it is expressed as a preprotein that participates in thesecretion of the polypeptide; a promoter or enhancer is operably linkedto a coding sequence if it affects the transcription of the sequence; ora ribosome binding site is operably linked to a coding sequence if it ispositioned so as to facilitate translation. Generally, “operably linked”means that the nucleic acid molecules being linked are contiguous, and,in the case of a secretory leader, contiguous and in reading phase.However, enhancers do not have to be contiguous. Linking is accomplishedby ligation at convenient restriction sites. If such sites do not exist,the synthetic oligonucleotide adaptors or linkers are used in accordancewith conventional practice.

As used herein, the expressions “cell”, “cell line”, and “cell culture”are used interchangeably and all such designations include progeny.Thus, the words “transformants” and “transformed cells” include theprimary subject cell and cultures derived there from without regard forthe number of transfers. It is also understood that all progeny may notbe precisely identical in DNA content, due to deliberate or inadvertentmutations. Mutant progeny that have the same function or biologicalactivity as screened for in the originally transformed cell areincluded. Where distinct designations are intended, it will be clearfrom the context.

A “patentable” composition, process, machine, or article of manufactureaccording to the invention means that the subject matter satisfies allstatutory requirements for patentability at the time the analysis isperformed. For example, with regard to novelty, non-obviousness, or thelike, if later investigation reveals that one or more claims encompassone or more embodiments that would negate novelty, non-obviousness,etc., the claim(s), being limited by definition to “patentable”embodiments, specifically exclude the unpatentable embodiment(s). Also,the claims appended hereto are to be interpreted both to provide thebroadest reasonable scope, as well as to preserve their validity.Furthermore, the claims are to be interpreted in a way that (1)preserves their validity and (2) provides the broadest reasonableinterpretation under the circumstances, if one or more of the statutoryrequirements for patentability are amended or if the standards changefor assessing whether a particular statutory requirement forpatentability is satisfied from the time this application is filed orissues as a patent to a time the validity of one or more of the appendedclaims is questioned.

The term “pharmaceutically acceptable salt” refers to salts which retainthe biological effectiveness and properties of the agents and compoundsof this invention and which are not biologically or otherwiseundesirable. In many cases, the agents and compounds of this inventionare capable of forming acid and/or base salts by virtue of the presenceof charged groups, for example, charged amino and/or carboxyl groups orgroups similar thereto. Pharmaceutically acceptable acid addition saltsmay be prepared from inorganic and organic acids, while pharmaceuticallyacceptable base addition salts can be prepared from inorganic andorganic bases. For a review of pharmaceutically acceptable salts (seeBerge, et al. (1977) J. Pharm. Sci., vol. 66, 1-19).

A “plurality” means more than one.

The terms “separated”, “purified”, “isolated”, and the like mean thatone or more components of a sample contained in a sample-holding vesselare or have been physically removed from, or diluted in the presence of,one or more other sample components present in the vessel. Samplecomponents that may be removed or diluted during a separating orpurifying step include, chemical reaction products, unreacted chemicals,proteins, carbohydrates, lipids, and unbound molecules.

The term “species” is used herein in various contexts, e.g., aparticular species of chemotherapeutic agent. In each context, the termrefers to a population of chemically indistinct molecules of the sortreferred in the particular context.

“Specifically associate” and “specific association” and the like referto a specific, non-random interaction between two molecules, whichinteraction depends on the presence of structural,hydrophobic/hydrophilic, and/or electrostatic features that allowappropriate chemical or molecular interactions between the molecules.

A “subject” or “patient” refers to an animal in need of treatment thatcan be effected by molecules of the invention. Animals that can betreated in accordance with the invention include vertebrates, withmammals such as bovine, canine, equine, feline, ovine, porcine, andprimate (including humans and non-human primates) animals beingparticularly preferred examples.

A “therapeutically effective amount” (or “effective amount”) refers toan amount of an active ingredient, e.g., an agent according to theinvention, sufficient to effect treatment when administered to a subjector patient. Accordingly, what constitutes a therapeutically effectiveamount of a composition according to the invention may be readilydetermined by one of ordinary skill in the art. In the context of oculartherapy, a “therapeutically effective amount” is one that produces anobjectively measured change in one or more parameters associated withtreatment of the ocular disease or condition including an increase ordecrease in the expression of one or more genes correlated with theocular disease or condition, induction of apoptosis or other cell deathpathways, clinical improvement in symptoms, a decrease in aberrantneovascularization or in inflammation, etc. Of course, thetherapeutically effective amount will vary depending upon the particularsubject and condition being treated, the weight and age of the subject,the severity of the disease condition, the particular compound chosen,the dosing regimen to be followed, timing of administration, the mannerof administration and the like, all of which can readily be determinedby one of ordinary skill in the art. It will be appreciated that in thecontext of combination therapy, what constitutes a therapeuticallyeffective amount of a particular active ingredient may differ from whatconstitutes a therapeutically effective amount of the active ingredientwhen administered as a monotherapy (ie., a therapeutic regimen thatemploys only one chemical entity as the active ingredient).

The term “treatment” or “treating” of a disease or disorder includespreventing or protecting against the disease or disorder (that is,causing the clinical symptoms not to develop); inhibiting the disease ordisorder (i.e., arresting or suppressing the development of clinicalsymptoms; and/or relieving the disease or disorder (i. e., causing theregression of clinical symptoms). As will be appreciated, it is notalways possible to distinguish between “preventing” and “suppressing” adisease or disorder since the ultimate inductive event or events may beunknown or latent. Accordingly, the term “prophylaxis” will beunderstood to constitute a type of “treatment” that encompasses both“preventing” and “suppressing.” The term “treatment” thus includes“prophylaxis”.

The term “therapeutic regimen” means any treatment of a disease ordisorder using chemotherapeutic drugs, radiation therapy, surgery, genetherapy, DNA vaccines and therapy, antisense-based therapies includingsiRNA therapy, anti-angiogenic therapy, immunotherapy, bone marrowtransplants, aptamers and other biologics such as antibodies andantibody variants, receptor decoys and other protein-based therapeutics.

SUMMARY OF THE INVENTION

This invention concerns patentable humanized anti-sphingolipid agents,including antibodies and anti-sphingolipid antibody variants withdesirable properties from a therapeutic and/or diagnostic perspective,including strong binding affinity for sphingolipids, the ability to bindand neutralize sphingosine-1-phosphate (S1P), particularly inphysiological contexts (e.g., in living tissue, blood, etc.) and underphysiological conditions, as well as isoforms, variants, isomers, andrelated compounds. In particular, the invention is drawn to antibodies,particularly monoclonal antibodies, more particularly humanizedmonoclonal antibodies and variants thereof, directed to S1P. Suchantibodies and variants are preferably included in pharmaceuticalcompositions suitable for administration to subjects known or suspectedto need treatment with such compounds. In addition to compositions, theinvention also provides methods of treatment using such agents.

In one embodiment, humanized antibodies or antigen binding fragmentsthereof are provided, which are specifically reactive with S1P andcomprise at least one heavy chain and at least one light chain, Eachheavy chain comprises a heavy chain variable domain comprising:asequence of amino acid residues having an amino acid sequence of SEQ IDNO: 27; or an amino acid sequence having at least about 80% sequenceidentity to it, and each light chain comprises a light chain variabledomain comprising a sequence of amino acid residues having an amino acidsequence of SEQ ID NO: 29 or an amino acid sequence having at leastabout 80% sequence identity to it.

Each heavy chain of these humanized antibodies or antigen bindingfragments thereof may comprise a first sequence of amino acid residuesof sequence DHTIH [SEQ ID NO:13]; a second sequence of amino acidresidues AISPRHDITKYNEMFRG [SEQ ID NO:18]; or a third sequence of aminoacid residues of sequence GGFYGSTIWFDF [SEQ ID NO: 15]; while each lightchain comprises a first sequence of amino acid residues of sequenceITTTDIDDDMN [SEQ ID NO:10]; a second sequence of amino acid residues ofsequence EGNILRP [SEQ ID NO:11]; or a third sequence of amino acidresidues of sequence LQSDNLPFT [SEQ ID NO:12].

The humanized antibodies of the invention may comprise a full lengthheavy chain amino acid sequence of SEQ ID NO: 31 and a full length lightchain amino acid sequence of SEQ ID NO: 32, or sequences having at leastabout 80% identity to these, including a heavy chain amino acid sequenceof SEQ ID NO: 35, which lacks a C-terminal lysine.

According to the invention the humanized antibody may comprise the sameheavy and light chain variable domain sequences as the heavy and lightchain variable domain sequences encoded by vector pATH1009 in ATCCAccession No. PTA-8421 or PTA-8422.

Further provided are pharmaceutical compositions comprising thehumanized antibodies or antigen binding fragments of the invention,nucleic acids encoding the humanized antibodies or antigen bindingfragments of the invention, host cells transfected with said nucleicacids, and methods of treating diseases or disorders correlated with anaberrant level of S1P using the compositions of the invention.

These and other aspects and embodiments of the invention are discussedin greater detail in the sections that follow. The foregoing and otheraspects of the invention will become more apparent from the followingdetailed description, accompanying drawings, and the claims. Althoughmethods and materials similar or equivalent to those described hereincan be used in the practice or testing of the present invention,suitable methods and materials are described below. In addition, thematerials, methods, and examples below are illustrative only and notintended to be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

This application contains at least one figure executed in color. Copiesof this application with color drawing(s) will be provided upon requestand payment of the necessary fee. A brief summary of each of the figuresis provided below.

FIG. 1. FIG. 1 has two panels, A and B. shows Panel A graphicallyillustrates the results of a competitive ELISA for S1P, SPH, LPA, SPC,and other structurally similar biolipids competing for abiotin-conjugated anti-S1P monoclonal antibody. These results indicatethat the antibody is specific and sensitive for S1P and does notrecognize structurally similar bioactive lipids. As described in Example1, below, bound antibody was detected by a second antibody, specific forthe mouse or human IgG, conjugated with HRP. Chromogenic reactions weremeasured and reported as optical density (OD). The concentration oflipids used for the competition is indicated on the X-axis. Nointeraction of the secondary antibody with S1P coated matrix alone couldbe detected (data not shown). Panel B shows the structures of thebioactive lipids similar to S1P that are listed in Panel A.

FIG. 2. This figure shows the binding properties of several chimeric andrecombinant humanized anti-SiP antibody variants. The binding to S1P fora chimeric antibody (pATH10+pATH50) was compared in an ELISA bindingassay to two versions of the humanized anti-S1P monoclonal antibody(pATH201+pATH308) and (pATH201+pATH309). pATH308 is the humanized lightchain with five murine backmutations and pATH309 is the humanized lightchain with three backmutations in the framework region. The humanizedheavy chain (pATH201) contains only one murine backmutation in theframework region.

FIG. 3 is a graph showing that SPHINGOMAB is highly specific for S1P.The graph, the data for which were generated using a competitive ELISA,demonstrates SPHINGOMAB's specificity for S1P as compared to otherbioactive lipids. SPHINGOMAB demonstrated no cross-reactivity tosphingosine (SPH), the immediate metabolic precursor of S1P orlysophosphatidic acid (LPA), an important extracellular signalingmolecule that is structurally and functionally similar to S1P.SPHINGOMAB did not recognize other structurally similar lipids andmetabolites, including ceramide-1-phosphate (C IP), dihydrosphingosine(DH-SPH), phosphatidyl serine (PS), phosphatidyl ethanolamine (PE), orsphingomyelin (SM). SPHINGOMAB did cross react withdihydrosphingosine-1-phosphate (DH-S1P) and, to a lesser extent,sphingosylphoryl choline (SPC). The affinity (Kd) of SPHINGOMAB for S1Pis less than 100 pM, much higher than most therapeutic antibodies,particularly other molecular sponges.

FIG. 4. FIG. 4 has two parts, A and B. The experiments giving rise tothe data represented in this Figure are detailed in Example 4, below.Briefly, these data show that SPHINGOMAB reduced CNV and scar formationin ocular lesions. Mice were treated with SPHINGOMAB or anisotype-matched non-specific monoclonal antibody. CNV lesions wereinduced by laser rupture of Bruchs membrane. Shown are graphs andrepresentative images of lesions from each treatment group stained withrhodamine-conjugated R. communis agglutinin I for vascularization (A) orMasson's Trichrome for collagen scar formation (B). FIG. 4A shows thatin a murine CNV lesion formation model SPHINGOMAB dramaticallyattenuates choroidal neovascularization 14 and 28 days afterlaser-induced rupture of Bruch's membranes. FIG. 4B shows thatSPHINGOMAB significantly reduces fibrosis associated with CNV lesionformation 28 days after laser-induced rupture of Bruchs's membrane.

FIG. 5. FIG. 5 has two panels, A and B. In panel A, S1P is shown topromote neovascularization through induction of HUVECs tube formationand migration, which is reduced by SPHINGOMAB. Panel 5A shows fourmicrographs of HUVECs seeded on Matrigel and incubated for 6 hr. toevaluate tube formation. Panel 5B shows data for HUVECs that weretreated with 1 μM S1P±SPHINGOMAB (1 μg/ml) for 6 hr. in a Matrigelinvasion chamber. The number of cells that migrated to the Matrigelmembrane were counted in five independent fields.

FIG. 6. FIG. 6 contains several photographs (A) and graphs (B and C) forexperiments described in Example, 6, below, which were performed usingSPHINGOMAB. SPHINGOMAB neutralizes S1P-, VEGF- and bFGF-inducedneovascularization. FIG. 6A shows photos of several representativeFITC-stained blood vessels from sections of Matrigel plugs±the indicatedgrowth factors. FIG. 6B shows that S1P stimulates endothelial cell (EC)infiltration. FIG. 6C represents the quantification of relativefluorescence from Matrigel plugs stimulated with VEGF or bFGF as anindicator of neovascularization. The effects of S1P, VEGF, and bFGF wereinhibited when mice were systemically treated with 1 or 25 mg/kg ofSPHINGOMAB.

FIG. 7. FIG. 7 shows 5 graphs, labeled A-E, and two pcolor photos. Thisdata was generated using the anti-S1P monoclonal antibody SPHINGOMAB.See Example 7, below, for experimental details. Briefly, these data showthat SPHINGOMAB neutralizes S1P-stimulated scar formation. In theseexperiemnts, fibroblasts were serum-starved and then treated with 0, 0.1, 0.5, or 1 μM S1P±1 μg/mL SPHINGOMAB for 12-24 hr. The data showS1P-stimulated Swiss 3T3 fibroblast proliferation, as measured by3H-thymidine incorporation (A), murine cardiac fibroblast migration in ascratch assay (B), collagen gene expression (relative fluorescence) inisolated cardiac fibroblasts from transgenic mice expressingcollagen-GFP (C), and WI-38 cell differentiation into myofibroblasts asmeasured by decreased cellular proliferation and increased α-SMAexpression (D). SPHINGOMAB neutralized each of these S1P effects.SPHINGOMAB reduced perivascular fibrosis in vivo in a murine model of apermanent myocardial infarction (E).

FIG. 8. FIG. 8 has three panel, 8A, 8B, and 8C. These data show that S1Ppromotes transformation of ocular epithelial cells and fibroblasts intocontractile, scar tissue-producing myofibroblasts. As described inExample 8, below, the effects of S1P on myofibroblast transformation ofseveral human ocular cell lines were examined. S1P was found tostimulate production of α-Smooth muscle actin (α-SMA; a myofibroblastmarker) in human retinal pigmented epithelial cells (FIG. 8A) and humanconjunctiva fibroblasts (FIG. 8B). These data demonstrate, for the firsttime, that S1P is among the factors that promote transformation ofocular epithelial cells and fibroblasts into contractile, scartissue-producing myofibroblasts. The effects of S1P on expression ofplasminogen activator inhibitor (PAI-1) in human conjunctiva fibroblastswere also examined. Increased PAI-1 expression correlates with adecrease in the proteolytic degradation of connective tissue and isupregulated in association with several fibrotic diseases that involveincreased scarring. As shown in FIG. 8C, S1P stimulates the PAI-1expression in a dose-dependent manner.

FIG. 9. FIG. 9 shows two bar graphs, A and B, showing experimental datagenerated using an anti-S1P monoclonal antibody called SPHINGOMAB.SPHINGOMAB reduced immune-cell wound infiltration in vivo. Mice weresubjected to MI, treated with saline or 25 mg/kg SPHINGOMAB 48 hr. aftersurgery and then sacrificed on day 4. SPHINGOMAB reduced macrophage (A)and mast cell (B) infiltration into the wound. Data are represented asfold decrease of saline-treated values.

FIG. 10. FIG. 10 has two panels, 10A and 10B. Each panel show a map of acloning vector for expression of murine anti-S1P monoclonal antibody VLand VH domains. FIG. 10A is a map of a pKN100 vector for the cloning ofthe VL domain. FIG. 10A is a map of a pGID200 vector for the cloning ofthe VH domain.

FIG. 11. FIG. 11 presents data showing the binding properties of severalmurine, chimeric, and recombinant humanized anti-S1P antibodies. Thebinding to S1P for the mouse (muMAbS1P; curve generated from square datapoints) and chimeric (chMAb S1P; curve generated from upright triangulardata points) were compared in an ELISA binding assay to the firstversion of the humanized antibody (pATH200+pATH300; curve generated frominverted triangular data points).

FIG. 12. FIG. 12 has two panels, A and B, that show data from in vitrocell assays performed using several humanized monoclonal antibodyvariants. Panel A shows the humanized mAb is able to prevent S1P fromprotecting SKOV3 cells from Taxol-induced apoptosis. As described inExample 16, below, SKOV3 cells were treated for 48 hr. with 500 nM Taxol(Tax) in the presence or absence of 500 nM S1P with huMAbHCLC₃ (309),huMAbHCLC₅ (308), muMAb S1P (muMAb), or non-specific IgG1 (NS) at aconcentration of 1 μg/mL. Values represent means±SEM (n=3) withtriplicates run for each data point. “NT” means not treated, and “Veh”stands for vehicle only. Panel B shows IL-8 secretion in ovarian cancer(OVCAR3) cells treated with S1P and one of several different theanti-SiP monoclonal antibodies or a control monoclonal antibody. In theexperiments described in detail in Example 16, below, 100,000 OVCAR3cells/well were starved overnight and 1 uM S1P was added to the culturemedia alone or pre-incubated with lug/ml of non-specific antibody (NS),pATH201+pATH309 (LC3), pATH201+pATH308 (LC5), pATH207+pATH309 (cysLC3),pATH207+pATH308 (cysLC5), and 0.1 μg/ml (M0.1), 1 μg/ml (M1) or 10 μg/ml(M10) of anti-S1P murine antibody. After 22 hours of incubation, cellsupernatants were collected and IL-8 secretion was measured by ELISAusing an R&D system Quantikine human CXCL8/IL-8 kit. In the figure “NT”refers to non-treated cells.

FIG. 13. FIG. 13 shows the in vivo efficacy of several human monoclonalantibody variants as compared to a mouse anti-S1P monoclonal antibodyand controls in a CNV animal model. As described in Example 17, below,in these experiments mice were administered with 0.5ug twice (day 0 andday 6) of a murine (Mu) anti-S1P monoclonal antibody, several humanizedanti-S1P monoclonal antibody variants (i.e., variants LC3, LC5,HCcysLC3, and HCcysLC5), or a non-specific monoclonal antibody (NS) byintravitreal administration and then subjected to laser rupture of theBruch's membrane. Mice were sacrificed 14 days post-laser surgery.Sclera-RPE-choroid complexes were dissected and stained with aRhodamine-conjugated R. communis agglutinin I antibody. CNV lesionvolumes are represented as the means±SEM.

FIG. 14. FIG. 14 is a series of line graphs showing the reduction ofcarryover of S1P in preparations of anti-S1P monoclonal antibody usingmethods of the invention to disrupt the LT1009-S1P binding. A) Effect ofEDTA on LT1009 binding S1P using direct-binding ELISA. B) pH titrationof a murine anti-S1P antibody binding S1P. C) pH titration of murineanti-LPA antibody binding LPA.

FIG. 15. FIG. 15 contains four graphs that show the percent purity ofvarious formulation samples that contain 11 mg/mL of the LT1009antibody. The data plotted were obtained via SE-HPLC, and the results ofthe studied formulations at time zero, 0.5 month, 1 month and 2 months.On each graph, the abscissa indicates the percent-purity of eachdepicted data point. Starting from the bottom, the first 6 points on theordinate in each graph are the results for pH 6.0; points 7 to 12 arethe results for pH 6.5; and points 13 to 18 depict the results for pH7.0. Likewise, the first three points from the bottom show the resultsfor 200 ppm polysorbate-80 at pH 6.0, the next three points (4 to 6)depict the results for 500 ppm polysorbate-80 at pH 6.0, the next threepoints (7 to 9) depict the results for 200 ppm polysorbate-80 at pH 6.5,etc. The effect of the salt condition is depicted in groups of three.The first point of each group from the bottom represents the 148 mM NaClcondition, the next point (2) represents the 300 mM NaCl condition andthe third point from the bottom represents the 450 mM NaCl condition andso on.

DETAILED DESCRIPTION OF THE INVENTION

1. Compounds.

The present invention describes certain anti-S1P agents, particularlythose that are immune-derived moieties, including antibodies, which arespecifically reactive with the bioactive lipid S1P; in other words, thebioactive lipid to which the anti-S1P agent reacts is S1P.

Antibody molecules or immunoglobulins are large glycoprotein moleculeswith a molecular weight of approximately 150 kDa, usually composed oftwo different kinds of polypeptide chain. One polypeptide chain, termedthe “heavy” chain (H) is approximately 50 kDa. The other polypeptide,termed the “light” chain (L), is approximately 25 kDa. Eachimmunoglobulin molecule usually consists of two heavy chains and twolight chains. The two heavy chains are linked to each other by disulfidebonds, the number of which varies between the heavy chains of differentimmunoglobulin isotypes. Each light chain is linked to a heavy chain byone covalent disulfide bond. In any given naturally occurring antibodymolecule, the two heavy chains and the two light chains are identical,harboring two identical antigen-binding sites, and are thus said to bedivalent, i.e., having the capacity to bind simultaneously to twoidentical molecules.

The “light” chains of antibody molecules from any vertebrate species canbe assigned to one of two clearly distinct types, kappa (k) and lambda(l), based on the amino acid sequences of their constant domains. Theratio of the two types of light chain varies from species to species. Asa way of example, the average k to l ratio is 20:1 in mice, whereas inhumans it is 2:1 and in cattle it is 1:20.

The “heavy” chains of antibody molecules from any vertebrate species canbe assigned to one of five clearly distinct types, called isotypes,based on the amino acid sequences of their constant domains. Someisotypes have several subtypes. The five major classes of immunoglobulinare immunoglobulin M (IgM), immunoglobulin D (IgD), immunoglobulin G(IgG), immunoglobulin A (IgA), and immunoglobulin E (IgE). IgG is themost abundant isotype and has several subclasses (IgG1, 2, 3, and 4 inhumans). The Fc fragment and hinge regions differ in antibodies ofdifferent isotypes, thus determining their functional properties.However, the overall organization of the domains is similar in allisotypes.

The term “variable region” refers to the N-terminal portion of theantibody molecule or a fragment thereof. In general, each of the fourchains has a variable (V) region in its amino terminal portion, whichcontributes to the antigen-binding site, and a constant (C) region,which determines the isotype. The light chains are bound to the heavychains by many noncovalent interactions and by disulfide bonds and the Vregions of the heavy and light chains pair in each arm of antibodymolecule to generate two identical antigen-binding sites. Some aminoacid residues are believed to form an interface between the light- andheavy-chain variable domains [see Kabat, et al. (1991), Sequences ofProteins of Immunological Interest, Fifth Edition, National Institute ofHealth, Bethesda, Md. and Clothia et al. (1985), J. Mol. Biol, vol 186:651].

Of note, variability is not uniformly distributed throughout thevariable domains of antibodies, but is concentrated in three segmentscalled “complementarity-determining regions” (CDRs) or “hypervariableregions” both in the light-chain and the heavy-chain variable domains.The more highly conserved portions of variable domains are called the“framework region” (FR). The variable domains of native heavy and lightchains each comprise four FR regions connected by three CDRs. The CDRsin each chain are held together in close proximity by the FR regionsand, with the CDRs from the other chains, form the antigen-binding siteof antibodies [see Kabat, et al. (1991), Sequences of Proteins ofImmunological Interest, Fifth Edition, National Institute of Health,Bethesda, Md.]. Collectively, the 6 CDRs contribute to the bindingproperties of the antibody molecule for the antigen. However, even asingle variable domain (or half of an Fv, comprising only three CDRsspecific for an antigen) has the ability to recognize and bind antigen[see Pluckthun (1994), in The Pharmacology of Monoclonal Antibodies,vol. 113, Rosenburg and Moore eds., Springer-Verlag, New York, pp.269-315].

The term “constant domain” refers to the C-terminal region of anantibody heavy or light chain. Generally, the constant domains are notdirectly involved in the binding properties of an antibody molecule toan antigen, but exhibit various effector functions, such asparticipation of the antibody in antibody-dependent cellular toxicity.Here, “effector functions” refer to the different physiological effectsof antibodies (e.g., opsonization, cell lysis, mast cell, basophil andeosinophil degranulation, and other processes) mediated by therecruitment of immune cells by the molecular interaction between the Fcdomain and proteins of the immune system. The isotype of the heavy chaindetermines the functional properties of the antibody. Their distinctivefunctional properties are conferred by the carboxy-terminal portions ofthe heavy chains, where they are not associated with light chains.

As used herein, “antibody fragment” refers to a portion of an intactantibody that includes the antigen binding site or variable regions ofan intact antibody, wherein the portion can be free of the constantheavy chain domains (e.g., CH2, CH3, and CH4) of the Fc region of theintact antibody. Alternatively, portions of the constant heavy chaindomains (e.g., CH2, CH3, and CH4) can be included in the “antibodyfragment”. Examples of antibody fragments are those that retainantigen-binding and include Fab, Fab′, F(ab′)2, Fd, and Fv fragments;diabodies; triabodies; single-chain antibody molecules (sc-Fv);minibodies, nanobodies, and multispecific antibodies formed fromantibody fragments. By way of example, a Fab fragment also contains theconstant domain of a light chain and the first constant domain (CH1) ofa heavy chain.

The term “variant” refers to an amino acid sequence which differs fromthe native amino acid sequence of an antibody by at least one amino acidresidue or modification. A native or parent or wild-type amino acidsequence refers to the amino acid sequence of an antibody found innature. “Variant” of the antibody molecule includes, but is not limitedto, changes within a variable region or a constant region of a lightchain and/or a heavy chain, including the hypervariable or CDR region,the Fc region, the Fab region, the CH1 domain, the CH2 domain, the CH3domain, and the hinge region.

The term “specific” refers to the selective binding of an antibody toits target epitope. Antibody molecules can be tested for specificity ofbinding by comparing binding of the antibody to the desired antigen tobinding of the antibody to unrelated antigen or analogue antigen orantigen mixture under a given set of conditions. Preferably, an antibodyaccording to the invention will lack significant binding to unrelatedantigens, or even analogs of the target antigen. Here, the term“antigen” refers to a molecule that is recognized and bound by anantibody molecule or immune-derived moiety that binds to the antigen.The specific portion of an antigen that is bound by an antibody istermed the “epitope.” A “hapten” refers to a small molecule that can,under most circumstances, elicit an immune response (i.e., act as anantigen) only when attached to a carrier molecule, for example, aprotein, polyethylene glycol (PEG), colloidal gold, silicone beads, andthe like. The carrier may be one that also does not elicit an immuneresponse by itself.

The term “antibody” is used in the broadest sense, and encompassesmonoclonal, polyclonal, multispecific (e.g., bispecific, wherein eacharm of the antibody is reactive with a different epitope or the same ordifferent antigen), minibody, heteroconjugate, diabody, triabody,chimeric, and synthetic antibodies, as well as antibody fragments thatspecifically bind an antigen with a desired binding property and/orbiological activity.

The term “monoclonal antibody” (mAb) refers to an antibody, orpopulation of like antibodies, obtained from a population ofsubstantially homogeneous antibodies, and is not to be construed asrequiring production of the antibody by any particular method. Forexample, monoclonal antibodies can be made by the hybridoma method firstdescribed by Kohler and Milstein (1975), Nature, vol 256: 495-497, or byrecombinant DNA methods.

The term “chimeric” antibody (or immunoglobulin) refers to a moleculecomprising a heavy and/or light chain which is identical with orhomologous to corresponding sequences in antibodies derived from aparticular species or belonging to a particular antibody class orsubclass, while the remainder of the chain(s) is identical with orhomologous to corresponding sequences in antibodies derived from anotherspecies or belonging to another antibody class or subclass, as well asfragments of such antibodies, so long as they exhibit the desiredbiological activity [Cabilly et al. (1984), infra; Morrison et al.,Proc. Natl. Acad. Sci. U.S.A. 81:6851].

The term “humanized antibody” refers to forms of antibodies that containsequences from non-human (eg, murine) antibodies as well as humanantibodies. A humanized antibody can include conservative amino acidsubstitutions or non-natural residues from the same or different speciesthat do not significantly alter its binding and/or biologic activity.Such antibodies are chimeric antibodies that contain minimal sequencederived from non-human immunoglobulins. For the most part, humanizedantibodies are human immunoglobulins (recipient antibody) in whichresidues from a complementary-determining region (CDR) of the recipientare replaced by residues from a CDR of a non-human species (donorantibody) such as mouse, rat, camel, bovine, goat, or rabbit having thedesired properties. Furthermore, humanized antibodies can compriseresidues that are found neither in the recipient antibody nor in theimported CDR or framework sequences. These modifications are made tofurther refine and maximize antibody performance. Thus, in general, ahumanized antibody will comprise all of at least one, and in one aspecttwo, variable domains, in which all or all of the hypervariable loopscorrespond to those of a non-human immunoglobulin and all orsubstantially all of the FR regions are those of a human immunoglobulinsequence. The humanized antibody optionally also will comprise at leasta portion of an immunoglobulin constant region (Fc), or that of a humanimmunoglobulin. See, e.g., Cabilly et al., U.S. Pat. No. 4,816,567;Cabilly et al., European Patent No. 0,125,023 B1; Boss et al., U.S. Pat.No. 4,816,397; Boss et al., European Patent No. 0,120,694 B1; Neuberger,M. S. et al., WO 86/01533; Neuberger, M. S. et al., European Patent No.0,194,276 B1; Winter, U.S. Pat. No. 5,225,539; Winter, European PatentNo. 0,239,400 B1; Padlan, E. A. et al., European Patent Application No.0,519,596 A1; Queen et al. (1989) Proc. Nat'l Acad. Sci. USA, vol 86:10029-10033).

The term “bispecific antibody” can refer to an antibody, or a monoclonalantibody, having binding properties for at least two different epitopes.In one embodiment, the epitopes are from the same antigen. In anotherembodiment, the epitopes are from two different antigens. Methods formaking bispecific antibodies are known in the art. For example,bispecific antibodies can be produced recombinantly using theco-expression of two immunoglobulin heavy chain/light chain pairs.Alternatively, bispecific antibodies can be prepared using chemicallinkage. Bispecific antibodies include bispecific antibody fragments.

The term “heteroconjugate antibody” can refer to two covalently joinedantibodies. Such antibodies can be prepared using known methods insynthetic protein chemistry, including using crosslinking agents. Asused herein, the term “conjugate” refers to molecules formed by thecovalent attachment of one or more antibody fragment(s) or bindingmoieties to one or more polymer molecule(s).

The term “biologically active” refers to an antibody or antibodyfragment that is capable of binding the desired epitope and in some wayexerting a biologic effect. Biological effects include, but are notlimited to, the modulation of a growth signal, the modulation of ananti-apoptotic signal, the modulation of an apoptotic signal, themodulation of the effector function cascade, and modulation of otherligand interactions.

The term “recombinant DNA” refers to nucleic acids and gene productsexpressed therefrom that have been engineered, created, or modified byman. “Recombinant” polypeptides or proteins are polypeptides or proteinsproduced by recombinant DNA techniques, for example, from cellstransformed by an exogenous DNA construct encoding the desiredpolypeptide or protein. “Synthetic” polypeptides or proteins are thoseprepared by chemical synthesis.

The term “expression cassette” refers to a nucleotide molecule capableof effecting expression of a structural gene (i.e., a protein codingsequence, such as an antibody of the invention) in a host compatiblewith such sequences. Expression cassettes include at least a promoteroperably linked with the polypeptide-coding sequence, and, optionally,with other sequences, e.g., transcription termination signals.Additional regulatory elements necessary or helpful in effectingexpression may also be used, e.g., enhancers. Thus, expression cassettesinclude plasmids, expression vectors, recombinant viruses, any form ofrecombinant “naked DNA” vector, and the like.

Sources of antibody are not limited to those exemplified herein (e.g.,murine and humanized murine antibody). Antibodies may be raised in manyspecies including mammalian species (for example, mouse, rat, camel,bovine, goat, horse, guinea pig, hamster, sheep and rabbit) and birds(duck, chicken). Antibodies raised may derive from a different speciesfrom the animal in which they are raised. For example, the XenoMouse™(Abgenix, Inc., Fremont Calif.) produces fully human monoclonalantibodies. For certain purposes, native human antibodies, such asautoantibodies to S1P isolated from individuals who may show a titer ofsuch S1P autoantibody may be used. Alternatively, a human antibodysequence library may be used to generate antibodies comprising a humansequence.

2. Applications.

The invention is drawn to compositions and methods for treating orpreventing certain diseases and conditions, using one or moretherapeutic agents that alter the activity or concentration of one ormore undesired bioactive lipids, or precursors or metabolites thereof.The therapeutic methods and compositions of the invention act bychanging the effective concentration, i.e., the absolute, relative,effective and/or available concentration and/or activities, of certainundesired bioactive lipids. Lowering the effective concentration of thebioactive lipid may be said to “neutralize” the target lipid or itsundesired effects, including downstream effects. Here, “undesired”refers to a bioactive lipid that is unwanted due to its involvement in adisease process, for example, as a signaling molecule, or to an unwantedamount of a bioactive lipid which contributes to disease when present inexcess.

Without wishing to be bound by any particular theory, it is believedthat inappropriate concentrations of S1P and/or its metabolites ordownstream effectors, may cause or contribute to the development ofvarious diseases and disorders. As such, the compositions and methodscan be used to treat these diseases and disorders, particularly bydecreasing the effective in vivo concentration of a particular targetlipid, for example, S1P or its variants. In particular, it is believedthat the compositions and methods of the invention are useful intreating diseases characterized, at least in part, by aberrantneovascularization, angiogenesis, fibrogenesis, fibrosis, scarring,inflammation, and immune response.

Examples of several classes of diseases that may be treated inaccordance with the invention are described below. It will beappreciated that many disease and conditions are characterized, at leastin part, by multiple pathological processes (for example, bothpathological neovascularization and scarring) and that theclassifications provided herein are for descriptive convenience and donot limit the invention.

S1P and Hyperproliferative Disorders

One aspect of the invention concerns methods for treating ahyperproliferative disorder. These methods comprise administering to amammal (e.g., a bovine, canine, equine, ovine, or porcine animal,particularly a human) known or suspected to suffer from anS1P-associated hyperproliferative disorder a therapeutically effectiveamount of a composition comprising an agent that interferes with S1Pactivity, preferably in a pharmaceutically or veterinarily acceptablecarrier, as the intended application may require. S1P-associatedhyperproliferative disorders include neoplasias, disorder associatedwith endothelial cell proliferation, and disorders associated withfibrogenesis. Most often, the neoplasia will be a cancer. Typicaldisorders associated with endothelial cell proliferation areangiogenesis-dependent disorders, for example, cancers caused by a solidtumors, hematological tumors, and age-related macular degeneration.Disorders associated with fibrogenesis include those than involveaberrant cardiac remodeling, such as cardiac failure.

There are many known hyperproliferative disorders, in which cells ofvarious tissues and organs exhibit aberrant patterns of growth,proliferation, migration, signaling, senescence, and death. While anumber of treatments have been developed to address some of thesediseases, many still remain largely untreatable with existingtechnologies, while in other cases, while treatments are available, theyare frequently less than optimal and are seldom curative.

Cancer represents perhaps the most widely recognized class ofhyperproliferative disorders. Cancers are a devastating class ofdiseases, and together, they have a mortality rate second only tocardiovascular disease. Many cancers are not fully understood on amolecular level. As a result, cancer is a major focus of research anddevelopment programs for both the United States government andpharmaceutical companies. The result has been an unprecedented R&Deffort and the production of many valuable therapeutic agents to help inthe fight against cancer.

Unfortunately the enormous amount of cancer research has not been enoughto overcome the significant damage caused by cancer. There are stillover one million new cases of cancer diagnosed annually and over fivehundred thousand deaths in the United States alone. This is a dramaticdemonstration that even though an enormous effort has been put forth todiscover new therapeutics for cancer, effective therapeutic agents tocombat the disease remain elusive.

Cancer is now primarily treated with one or a combination of three typesof therapies, surgery, radiation, and chemotherapy. Surgery involves thebulk removal of diseased tissue. While surgery is sometimes effective inremoving tumors located at certain sites, for example, in the breast,colon, and skin, it cannot be used in the treatment of tumors located inother areas, such as the backbone, nor in the treatment of disseminatedneoplastic conditions such as leukemia. Radiation therapy involves theexposure of living tissue to ionizing radiation causing death or damageto the exposed cells. Side effects from radiation therapy may be acuteand temporary, while others may be irreversible. Chemotherapy involvesthe disruption of cell replication or cell metabolism.

Further insult is that current therapeutic agents usually involvesignificant drawbacks for the patient in the form of toxicity and severeside effects. Therefore, many groups have recently begun to look for newapproaches to fighting the war against cancer. These new so-called“innovative therapies” include gene therapy and therapeutic proteinssuch as monoclonal antibodies.

The first monoclonal used in the clinic for the treatment of cancer wasRituxan (rituximab) which was launched in 1997, and has demonstrated theutility of biospecific monoclonal antibodies as therapeutic agents.Thus, not surprisingly, sixteen other monoclonal antibodies have sincebeen approved for use in the clinic, including six that are prescribedfor cancer. The success of these products, as well as the reduced costand time to develop monoclonal antibodies as compared with smallmolecules has made monoclonal antibody therapeutics the second largestcategory of drug candidates behind small molecules. Further, theexquisite specificity of antibodies as compared to small moleculetherapeutics has proven to be a major advantage both in terms ofefficacy and toxicity. For cancer alone there are currently more than270 industry antibody R&D projects with more than 50 companies involvedin developing new cancer antibody therapeutics. Consequently, monoclonalantibodies are poised to become a major player in the treatment ofcancer and they are estimated to capture an increasing share of thecancer therapeutic market.

The identification of extracellular mediators that promote tumor growthand survival is a critical step in discovering therapeutic interventionsthat will reduce the morbidity and mortality of cancer. As describedbelow, sphingosine-1-phosphate (S1P), a key component of sphingolipidsignaling cascade, is considered to be a pleiotropic, tumorigenic growthfactor. S1P promotes tumor growth by stimulating cell proliferation,cell survival, and metastasis. S1P also promotes tumor angiogenesis bysupporting the migration and survival of endothelial cells as they formnew vessels within tumors. Taken together, S1P initiates aproliferative, pro-angiogenic, and anti-apoptotic sequence of eventscontributing to cancer progression. Thus, therapies that modulate, and,in particular, reduce S1P levels in vivo will be effective in thetreatment of cancer.

Research has demonstrated that sphingosine kinase (SPHK) is a recentlyvalidated oncogene that produces an extracellular sphingolipid signalingmolecule, sphingosine-1-phosphate (S1P) that promotes tumor growth.Tumor growth is promoted both directly and indirectly by S1P's growthfactor actions related to tumor cell proliferation and metastasis, aswell as S1P's pro-angiogenic effects. The applicant has produced abiospecific monoclonal anti-S1P antibody (anti-S1P mAb) that could beused as a therapeutic molecular sponge to selectively absorb S1P, thuslowering extracellular concentrations of this tumor growth factor withthe anticipated reduction in tumor volume and metastatic potential aswell as simultaneously blocking new blood vessel formation that would,otherwise, feed the growing tumor. The anticipated success of themolecular absorption concept will represent an innovative approach tothe treatment of cancer. As the paragraphs below will demonstrate, theapplicant has developed a mAb against an important tumor growth factor,sphingosine-1-phosphate (S1P). The applicant believes that this antibodycan be effective in reduced the proliferation, metastatic potential andangiogenesis associated with many cancer types, and therefore, cancer ingeneral as well as the tumor angiogenesis that accompanies the disease.

The neutral form of sphingomyelinase (nSMase) is a key early componentof the sphingolipid signaling pathway (Chatterjee, Adv. Lipid Res. 26:25-46, 1993; Liu, Obein, and Hannun, Semin. Cell Dev. Biol. 8: 311-322,1997) nSMase is only one of at least five classes of SMase that havebeen identified, including the alkaline, the acidic, the acidiczinc-dependent, the neutral magnesium-dependent, and the neutralmagnesium-independent (Liu, Obein, and Hannun, Semin. Cell Dev. Biol. 8:311-322, 1997). The nSMase class is commonly associated with surfacemembranes (Das, Cook, and Spence, Biochim Biophys Acta 777: 339-342,1984; Dobrowsky, Cell Signal 12: 81-90., 2000) and can be activated by avariety of stimuli to cause apoptosis, such as the pro-inflammatorycytokine, tumor necrosis factor alpha (TNFα) (Segui, et al., J. Clin.Invest. 108: 143-151, 2001), T cell receptor (Tonnetti, et al., J. Exp.Med 189: 1581-1589, 1999), ionizing radiation (Haimovitz-Friedman, etal., J. Exp. Med 180: 525-535, 1994) and the anthracyclineanti-neoplastic agents (Andrieu-Abadie, et al., FASEB J. 13: 1501-1510,1999). Tumor necrosis factor alpha (TNFα) is a well-known activator ofnSMase (Adam, et al., J. Bio Chem 271: 14617-14622, 1996; Dressler,Mathias, and Kolesnick, Science 255: 1715-1718, 1992; Kim, et al., J.Biol. Chem. 266:1: 484-489, 1991; Kronke, Chem Phys Lipids 102: 157-66.,1999; Yanaga and Watson, FEBS Letters 314: 297-300, 1992), CERproduction (Kronke, Chem Phys Lipids 102: 157-66., 1999) and apoptosis(Rath and Aggarwal, J. Clin. Immuno. 19: 350-364, 1999; Robaye, et al.,Am J Pathol 138: 447-453, 1991; Takeda et al., Int. Immunol. 5: 691-694,1993) in many cell types, including cancer cell lines (Andrieu-Abadie,et al., FASEB J. 13: 1501-1510, 1999; Hannun and Obein, Trends in Biol.Sci. 20: 72-76, 1995; Kolesnick, trends Biochem Sci 24: 224-5, 1999;Obeid, et al., Science 259: 1769-1771, 1993), and the activation ofnSMase has been shown to be critical for TNFα induced apoptosis(Luberto, et al., J. Biol. Chem. 277: 41128-41139, 2002; Segui, et al.,J. Clin. Invest. 108: 143-151, 2001). As a consequence, nSMase has alsobeen proposed as a target for drug discovery (Wascholowski and Giannis,Drug News Perspect. 14: 581-90, 2001).

The sphingolipid signaling molecule, S1P, is produced from SPH throughthe action of sphingosine kinase (SPHK). Two isoforms of the kinase havebeen identified, SPHK1 and SPHK2 (Liu, J Biol Chem 275: 19513-20, 2000;Nava, et al., Exp Cell Res 281: 115-127, 2002). While CER and SPH arecommonly associated with apoptosis, conversely S1P is a mediator of cellproliferation and activation of survival pathways (An, Ann N Y Acad Sci905: 25-33, 2000; Maceyka, et al., BBA 1585: 193-201, 2002; Zhang, etal., J. Cell Biol. 114: 155-167, 1991). It has recently been appreciatedas an extracellular mediator that can activate a set of G ProteinCoupled Receptors (GPCRS) belonging to the S1P/LPA receptor family,formerly known as Edg receptors (An, Ann N Y Acad Sci 905: 25-33, 2000;An, Goetzl, and Lee, J. cell biochem 30/31: 147-157, 1998; Lee, et al.,Science 279: 1552-1555, 1998; Okamoto, et al., Biochem. Biophys. Res.Commun. 260: 203-208, 1999); however, intracellular actions of S1P havealso been suggested (Van Brocklyn, et al., J. Cell Biol. 142: 229-240,1998). Moreover, it has been suggested that the balance between CER/SPHlevels versus S1P provides a rheostat mechanism that decides whether acell is sent into the death pathway or is protected from apoptosis(Kwon, et al., J Biol Chem 276: 10627-10633, 2001; Maceyka, et al., BBA1585: 193-201, 2002; Pyne, Biochem J. 349: 385-402, 2000). The keyregulatory enzyme of the rheostat mechanism is SPHK whose role is toconvert the death-promoting sphingolipids (CER/SPH) in to thegrowth-promoting S1P.

A landmark study first proposing SPHK as an oncogene was published by agroup from Adelaide demonstrating that NIH-3T3 fibroblasts stablytransfected with the kinase exhibited enhanced cell proliferationaccompanied by increased S1P production (Vadas and Gamble, Circ. Res.79: 1216-1217, 1996; Xia et al., Curr Biol 10: 1527-1530, 2000). Inaddition, the SPHK over-expressers escaped contact inhibition, aproperty commonly exhibited by transformed cells. This observation isconsistent with a recent report showing that S1P enhances metastaticpotential of selected human cancer cell lines (Igarashi, Ann. N.Y. Acad.Sci. 845: 19-31, 1998; Takuwa, Biochim Biophys Acta. 1582: 112-120,2002). Moreover, the transfectants produced tumors when injectedsubcutaneous into NOD/SCID mice. These results were recently confirmedin a study showing that a small molecule inhibitor of SPHK given i.p.could reduce tumor volume in SCID mice receiving subcutaneous injectionsof JC mammary adenocarcinoma cells (French, et al., Cancer Res 63:5962-5969, 2003). Significantly, the concept that SPHK could be a noveloncogene was cemented by the finding that SPHK was over-expressed inmany solid tumors, such as those of the breast, colon, lung, ovary,stomach, uterus, kidney, and rectum (French et al. (2003), above). Inaddition, it has been demonstrated that several human tumor-derived celllines could be driven into apoptosis when treated with the SPHK smallmolecule inhibitors, and that their effectiveness could be accounted forby their abilities to reduce S1P levels. Taken together, these findingsdemonstrate an important concept that S1P is a growth factor likelyproduced by tumor cells themselves and that lowering the concentrationof S1P may cause the apoptosis seen upon growth factor withdrawal.

S1P and Tumor Angiogenesis

Angiogenesis is the process by which new blood vessels are formed fromexisting vasculature. Angiogenesis plays a critical role in severalphysiological processes and is implicated in the pathogenesis of avariety of disorders, including tumor growth, invasion and metastasis.The angiogenesis process associated with solid and circulating tumors(tumor angiogenesis) is considered to be a crucial component oftumorigenesis and disease progression, with the new blood vesselsproviding a growth advantage to tumor cells compared to non-cancerouscells. Therefore, clinical control of angiogenesis is a criticalcomponent for the treatment of cancer and other angiogenesis-dependentdiseases. Anti-angiogenic therapeutics is particularly attractivebecause vascular endothelial cells (ECs) do not mutate as easily as docancer cells; consequently, ECs are less likely than cancer cells togain resistance to prolonged therapy, making them good potential targetsfor therapeutics.

Several growth factors have been implicated in cancerous angiogenesis.The biolipid sphingosine-1-phosphate (S1P) was found to be a mediator ofmany cellular processes important for cancer. S1P exerts most of itseffects as a specific ligand for a family of G-protein-coupledreceptors, designated S1P₁₋₅. These receptors regulate angiogenesis andvascular maturation, cell movement, and lymphocyte trafficking. Incontrast to S1P, the precursors to S1P, sphingosine and ceramide, havebeen associated with growth arrest and apoptosis. Finally, there is acomplex cross-talk between S1P and other pro-angiogenic growth factorssuch as VEGF, EGFGF, PDGF, bFGF and IL-8. S1P, by binding to receptorS1P_(1,) transactivates growth factor receptor tyrosine kinase, such asthat found on VEGFR, EGFR, and PDGFR. The importance of S1P in theangiogenesis-dependent tumors makes S1P an exceptional target for cancertreatment. Based on these observations, an antibody approach toneutralize the extracellular S1P could result in a marked decrease incancer progression in humans as a result of inhibition of blood vesselformation with concomitant loss of the nutrients and oxygen needed tosupport tumor growth. Furthermore, recent research suggests that manyangiogenesis inhibitors may also act as anti-invasive andanti-metastatic compounds which could also aid in the mitigation of thespread of cancer to sites distant from the initial tumor.

A growing body of recent evidence implicating S1P as one of the mostpotent pro-angiogenic agents comes from studies directly comparing S1Pwith agents such as VEGF and bFGF. S1P stimulates DNA synthesis andchemotactic motility of human venous endothelial cells (HUVECs), whileinducing differentiation of multicellular structures, all of which issuggestive of S1P's role in early blood-vessel formation (Argraves, etal., 2004; Lee et al., 1999; Liu, et al., 2000). Also, S1P promotes themigration of bone marrow-derived EC precursors to neovascularizationsites (Annabi, et al., 2003). Cells that over-express S1P₁ are resistantto the anti-angiogenic agents thalidomide and Neovastat (Annabi et al.,2003). In addition, it has been demonstrated that substantial cross-talkexists between S1P and other pro-angiogenic growth factors such as VEGF,EGF, PDGF, bFGF and IL-8. For example, S1P transactivates EGF (Shida, etal., 2004) and VEGF2 receptors (Spiegel & Milstien, 2003), and VEGFup-regulates S1P₁ receptor expression (Igarashi, et al., 2003). Also,S1P, acting via S1P₁ and the “VEGF axis,” is required for hind-limbangiogenesis and neovascularization (Chae, et al., 2004).

The anti-angiogenic approach to cancer has been greatly advanced by therecent FDA approval of the anti-angiogenic drug, bevacizumab (Avastin®,Genentech) to treat colon cancer as an adjunct to cytotoxicchemotherapy.

An anti-S1P murine MAb, LT1002 was developed recently with high bindingaffinity and specificity to S1P. LT1002 was shown to significantly slowtumor progression and associated angiogenesis in several animal modelsof human cancer. In addition, LT1002 attenuated choroidalneovascularization (CNV) lesion formation in the well-established modelof angiogenesis for age-related macular degeneration (AMD). CNV occursin diseases in which there are abnormalities of Bruch's membrane and theretinal pigmented epithelium. The most common disease of this type isAMD, the most prevalent cause of severe loss of vision in elderlypatients. These results suggested that LT1002 has several mechanisms ofaction, including: (1) direct effects on tumor cell growth, (2) anindirect anti-angiogenic effect on vascular endothelia cells, and (3) anindirect anti-angiogenic effect of preventing the release and action ofother pro-angiogenic growth factors.

The most direct in vivo evidence that S1P contributes to tumorangiogenesis comes from our recent publication that focused on a murinemonoclonal antibody (mAb) designed to neutralize extracellular S1P bymolecular absorption (Visentin, et al., 2006). In various in vitroassays using HUVECs, the anti-S1P mAb neutralized tube formation,migration of vascular endothelial cells and protection from cell death,each of which is S1P-induced. S1P increased new capillary growth intoMatrigel plugs implanted in mice, an effect that was neutralized by thesystemic administration of the anti-S1P mAb. The mAb substantiallyneutralized bFGF- and VEGF-induced angiogenesis in a murine Matrigelplug assay, and the antibody mitigated S1P stimulated the release ofpro-angiogenic cytokines (VEGF, IL-8, IL-6) from tumor cells in vitroand in vivo. Importantly, mice xenografted with orthotopically-placedhuman cancer cells exhibited substantial retardation of tumorprogression with anti-SiP mAb treatment. This was demonstrated in murinemodels of human breast, ovarian and lung cancer and in one allograftmodel of murine melanoma (Visentin, et al., 2006).

The use of monoclonal antibodies (mAbs) as a therapeutic treatment for avariety of diseases and disorders is rapidly increasing because theyhave been shown to be safe and efficacious therapeutic agents. Approvedtherapeutic mAbs include Avastin®, Erbitux®, and Rituxan®. AdditionalmAbs are in various phases of clinical development for a variety ofdiseases with the majority targeting various forms of cancer. Ingeneral, monoclonal antibodies are generated in non-human mammals. Thetherapeutic utility of murine monoclonal antibodies is limited, however,principally due to the fact that human patients mount their own antibodyresponse to murine antibodies. This response, the so-called HAMA (humananti-mouse antibody) response, results in the eventual neutralizationand rapid elimination of murine mAbs. This limitation has been overcomewith the development of a process called “humanization” of murineantibodies. Humanization greatly lessens the development of an immuneresponse against the administered therapeutic MAb and thereby avoids thereduction of half-life and therapeutic efficacy consequent on HAMA. Forthe most part, the humanization process consists of grafting the murinecomplementary determining regions (CDRs) into the framework region (FR)of a human immunoglobulin. This strategy is referred to as “CDRgrafting”. “Backmutation” to murine amino acid residues of selectedresidues in the human FR is often required to regain affinity that islost in the initial grafted construct.

The manufacture of mAbs is a complex process that stems from thevariability of the protein itself. The variability of mAbs can belocalized to the protein backbone and/or to the carbohydrate moiety. Theheterogeneity can be attributed to the formation of alternativedisulfide pairings, deamidation and the formation of isoaspartylresidues, methionine and cysteine oxidation, cyclization of N-terminalglutamine residues to pyroglutamate and partial enzymatic cleavage ofC-terminal lysines by mammalian carboxypeptidases. Engineering iscommonly applied to antibody molecules to improve their properties, suchas enhanced stability, resistance to proteases, aggregation behavior andenhance the expression level in heterologous systems.

Here, the humanization of the murine MAb against S1P is described. Theoverall strategy consisted of grafting the six CDRs from LT1002 into ahuman framework. Further modifications were engineered to further refineand optimize the antibody performance. The humanized MAb presented thesame characteristics as the LT1002 and is thus suitable for testing inclinical trials.

S1P and Fibrosis

Fibroblasts, particularly myofibroblasts, are key cellular elements inscar formation in response to cellular injury and inflammation [Tomasek,et al. (2002), Nat Rev Mol Cell Biol, vol 3: 349-63, and Virag and Murry(2003), Am J Pathol, vol 163: 2433-40]. Collagen gene expression bymyofibroblasts is a hallmark of remodeling and necessary for scarformation [Sun and Weber (2000), Cardiovasc Res, vol 46: 250-6, and Sunand Weber (1996), J Mol Cell Cardiol, vol 28: 851-8]. S1P promotes woundhealing by activating fibroblast migration and proliferation whileincreasing collagen production [Sun, et al. (1994), J Biol Chem, vol269: 16512-7]. S1P produced locally by damaged cells could beresponsible for the maladaptive wound healing associated with remodelingand scar formation. Thus it is believed that S1P inhibitors are usefulin diseases or conditions characterized, at least in part, by aberrantfibrogenesis or fibrosis. Herein, “fibrogenesis” is defined as excessiveactivity or number of fibroblasts, and “fibrosis” is defined asexcessive activity or number of fibroblasts that leads to excessive orinappropriate collagen production and scarring, destruction of thephysiological tissue structure and/or inappropriate contraction of thematrix leading to such pathologies as retinal detachment or otherprocesses leading to impairment of organ function.

S1P and fibroblast collagen expression: S1P promotes the differentiationof quiescent fibroblasts to active myofibroblasts which exhibit enhancedcollagen expression during scar formation [Urata, et al (2005), Kobe JMed Sci, vol 51: 17-27]. Concurrent with the proliferation and migrationof fibroblasts into the scarring zone, myofibroblasts deposit atemporary granular network consisting primarily of osteopontin andfibronectin [Sun and Weber (2000), Cardiovasc Res, vol 46: 250-6]. Asremodeling proceeds, the temporary matrix is absorbed and a collagennetwork established [Sun and Weber (2000), Cardiovasc Res, vol 46:250-6]. We have demonstrated that S1P promotes collagen production bymyofibroblasts. TGFβ, a well-known fibrotic mediator, has been shown toup-regulate several pro-fibrotic proteins, convert fibroblasts tomyofibroblasts and stimulate inflammatory protein expression possiblythrough the action of S1P [Squires, et al. (2005), J Mol Cell Cardiol,vol 39: 699-707 and Butt, Laurent and Bishop (1995), Eur J Cell Biol,vol 68: 330-5]. Up-regulation of TIMP1, a signaling molecule implicatedin TGFβ-stimulated differentiation of fibroblasts to myofibroblasts, isblocked by siRNA against SPHK1 [Yamanaka, et al., J Biol Chem. Dec. 24,2004;279(52):53994-4001], suggesting that a humanized version of theanti-S1P antibody could mitigate the profibrotic effects of TGFβ as wellas mitigating the fibrogenic effects of S1P itself.

Minimizing maladaptive scarring is believed to be useful in treatment offibrotic diseases and conditions, including but not limited to ocularand cardiovascular diseases, wound healing, and scleroderma.

Anti-S1P antibodies for the Treatment of Diseases and ConditionsCharacterized by an Aberrant Excessive or Undesired Immune Response

The immune system protects the body from potentially harmful substancessuch as microorganisms, toxins, cancer cells, and foreign blood or cellsfrom another person or species. These antigens are destroyed by theimmune response, which includes production of antibodies and sensitizedlymphocytes, which are specialized white blood cells that recognize anddestroy particular antigens.

Autoimmune disorders develop when the immune system destroys normal bodytissues, which it normally would ignore. Normally, the immune system iscapable of differentiating self from non-self tissue. Some lymphocytesbecome sensitized against self tissue cells, but this response isusually controlled or suppressed by other lymphocytes. Autoimmunedisorders occur when the normal control process is disrupted. Normally,most T cell lymphocytes that recognize self-antigens are eliminated inthe thymus, their site of origin, and never enter general circulation.The normal T cells circulate through the lymph nodes and the bloodwithout ever responding to self-antigens. However, it is believed thatpatients with autoimmune disorders bear T cells that can becomeactivated by self-antigens. Once activated, the T cell divides toproduce many effector cells which attack the activating antigen. Whenthe antigen is a self-antigen rather than a foreign antigen, serious andpotentially deadly consequences result. Autoimmune responses may alsooccur if normal body tissue is altered so that it is no longerrecognized as self.

Autoimmune disorders may result in destruction of one or more types ofbody tissues, abnormal growth of an organ, or changes in organ function.The disorder may affect only one organ or tissue type or may affectmultiple organs and tissues, depending on the identity of the activatingantigen. Organs and tissues commonly affected by autoimmune disordersinclude blood components such as red blood cells, blood vessels,connective tissues, nervous system, major organs, endocrine glands suchas the thyroid or pancreas, muscles, joints, and skin. A person mayexperience multiple autoimmune disorders at the same time.

Some nonlimiting examples of confirmed or suspected autoimmune diseasesand conditions include Type 1 diabetes mellitus, psoriasis, autoimmuneglomerulonephritis, autoimmune hemolytic anemia, acute disseminatedencephalomyelitis, Addison's disease, alopecia universalis, ankylosingspondylitis, antiphospholipid antibody syndrome, autoimmune oophoritis,autoimmune orchitis, autoimmune polyendocrine failure, Behcet disease,Berger's disease, Buergers disease, bullous pemphigus, celiac sprue,Chagas′ disease, Graves disease, Goodpastures syndrome, Guillain-Barresyndrome, Hashimato's thyroiditis, chronic active hepatitis, chronicfatigue syndrome, chronic progressive hepatitis, idiopathicthrombocytopenia purpura, Jobs syndrome, psoriatic arthritis, rheumatoidarthritis, Kawasaki's disease, multiple sclerosis, myasthenia gravis,pemphigoid, pemphigus, pemphigus erythematosus, pemphigus foliaceus,pemphigus vulgaris, polymyalgia rheumatica, pulmonary fibrosis, Reiterssyndrome, Reidel's thyroiditis, rheumatic fever, sarcoidosis, Sezarysyndrome; scleroderma, ulcerative colitis, autoimmune hemolytic anemia,Feltys syndrome, systemic lupus erythematosus, discoid lupuserythematosus, autoimmune polyarteritis nodosa, Caplans syndrome,Crohn's disease, dysautonomia, endometriosis, hydraadenitis suppurativa,interstitial cystitis, Lyme disease, postural orthostatic tachycardiasyndrome, opsoclonus myoclonus syndrome, psoriasis, Sjogren's syndrome,CREST syndrome, viral myocarditis, Wegener's granulomatosis andWiscott-Aldrich syndrome. Some of these disorders have been confirmed tobe autoimmune disorders by the presence of autoantibodies.

MS is an inflammatory disease of the CNS; onset occurs between the agesof 20 and 40 years and in the US, 350,000 people have MS. The course ofMS is generally characterized by acute exacerbations of neurologicsymptoms followed by a series of relapses and remissions. Theseexacerbations often result in permanent neurologic deficits. Although MSis not a fatal disease, disease progression often results in functionaldisability and reduced quality of life. Early symptoms of the diseasemay include oculomotor disturbances, tremor, ataxia, spasticity,fatigue, sensory disturbances, pain syndromes, bladder or boweldysfunction, and psychiatric disorders. Subsequent symptoms include moreprominent upper motor neuron disturbances, i.e., increased spasticity,increasing para- or quadriparesis. Vertigo, incoordination, depression,emotional lability, gait abnormalities, fatigue and pain are alsocommonly seen.

The precise pathogenesis of MS remains unknown; it is believed that Tcells in the peripheral circulation are activated by unknown antigensand cross the blood-brain barrier into the CNS. In the CNS, the T cellsstimulate production of proinflammatory cytokines that go on to causedemyelination with subsequent neurologic dysfunction. In particular,CD4+ T cells and macrophages destroy oligodendrocytes, which synthesizeand maintain axonal myelin sheaths in the central nervous system (CNS).

Treatment for MS patients takes various forms, including modification ofthe disease course, treatment of exacerbations (also called attacks,relapses, or flare-ups) and symptom management (both primary andsecondary), as well as improvement of function and safety, and emotionalsupport. Treatment of exacerbations (which are episodes of loss offunction stemming from new myelin damage) is often accomplished withhigh doses of corticosteroids to reduce inflammation. Some steroids,such as prednisone, are generally given orally. Others, such asmethylprednisolone and dexamethasone, are given intravenously.

In addition to motor paralysis and weakness, there are many primary andsecondary symptoms that affect persons with MS. These include fatigue,dizziness, nausea/vomiting, constipation, erectile dysfunction,paroxysmal itching, urinary tract infections, depression, neuropathicpain/dyesthesias, spasticity, urinary frequency, bladder dysfunction andtremors. Commonly used treatments for managing one or more of thesesymptoms include meclizine for dizziness and nausea/vomiting,antibiotics and antimicrobials for urinary tract infections,phenazopyridine for symptomatic relief of urinary tract infections,hydroxyzine for paroxysmal itching, papaverine, sildenafil, alprostadil,vardenafil or tadalafil for erectile dysfunction, docusate, psylliumfiber, glycerin suppositories, enemas, magnesium hydroxide, sodiumphosphate or bisacodyl for constipation, duloxetine hydrochloride fordepression or neuropathic pain, dantrolene for spasticity, desmopressin,oxybutynin, terazosin, prazosin, darifenacin, tamsulosin, oxybutynin,trospium chloride, imipramine, propantheline bromide, solifenacinsuccinate or tolterodine for urinary frequency or bladder dysfunction,phenytoin or gabapentin for dyesthesias, fluoxetine, venlafaxine,sertraline, bupropion or paroxetine for depression, amitryptyline forparesthesias, methenamine for preventing urinary tract infections,tizanidine, diazepam or baclofen for spasticity, clonazepam for tremor,pain, or spasticity, isoniazid for tremor, nortriptyline forparesthesias, modafinil or fluoxetine for fatigue, carbamazepine fortrigeminal neuralgia, and imipramine for pain.

Curative therapy is the ultimate goal in MS treatment; however, thisremains elusive since the underlying disease mechanism is unknown andthe disease presentation is heterogeneous. The Executive Committee ofthe Medical Advisory Board of the National MS Society has adopted thefollowing recommendations regarding the use of the current MS diseasemodifying agents, such as the immunomodulators Betaseron® (betainterferon 1b), Avonex® (beta interferon 1a), Rebif® (beta interferon1a), Copaxone® (glatiramer acetate), and Tysabri® (natalizumab); and theimmunosuppressant Novantrone® (mitoxantrone). The recommendations arethat immunomodulator treatment be initiated as soon as possiblefollowing the diagnosis of MS with a relapsing course.Immunosuppressants (mitoxantrone) may be considered for selectedworsening and/or relapsing patients. Therapy should be continuedindefinitely except in the event of clear lack of benefits, intolerableside effects, new data or better therapy. Thus there is an unmet medicalneed for better treatment of patients with MS.

Emerging treatments take into account the different immunopathologicalmechanisms as well as strategies to protect against axonal damage or topromote remyelination.

The immunosuppressant fingolimod (FTY720 or2-amino-2-(2-[4-octylphenyl]ethyl)-1,3-propanediol hydrochloride) hasshown to exert considerable therapeutic effects in clinical trialsinvolving patients with relapsing multiple sclerosis. Patients whoreceived oral fingolimod once daily had a rapid reduction in diseaseactivity, reflected in significant reductions in the relapse rate and inthe number of CNS lesions. FTY720 also interferes with T-cell migrationand prevents lymphocytes from leaving lymph nodes and other tissues. Thesequestration of T and B lymphocytes in lymphoid tissues results in thenearly complete disappearance of lymphocytes from the blood and thisprocess is reversible indicating that fingolimod does not killlymphocytes. As FTY720 enters the bloodstream, it is rapidlyphosphorylated. Phosphorylated FTY720 binds to all S1P receptors exceptS1P2. S1P1, the predominant S1P receptor expressed on lymphocytes, is amajor regulator of lymphocyte migration and is required forextravascular lymphocytes to emigrate from tissues. In the brain, Tcells are reactivated and induce a detrimental inflammatory reaction.FTY720 at 0.1 mg/kg p.o. or higher doses almost completely preventsparalysis in experimental autoimmune encephalomyelitis (EAE) induced bymyelin basic protein in LEW rats. Therapeutic treatment with FTY720inhibits EAE relapse induced by myelin proteolipid protein immunizationin SJL mice. Webb, M et al. (2004) J. Neuroimm. 153:108:121.

Natalizumab (Tysabri®), a monoclonal antibody that blocks the α4β1integrin-dependent adhesion of blood-borne encephalitogenic T cells andmacrophages to microvessels in the CNS block T cell migration. In theperipheral lymph nodes of patients with multiple sclerosis, autoreactiveCD4+ T cells are thought to encounter antigen-presenting dendritic cellsand differentiate into effector cells. The encephalitogenic T cellsleave the peripheral lymph nodes, gain access to the bloodstream andadhere to endothelial cells in the CNS, a step that is blocked bynatalizumab.

Applicant's a murine monoclonal anti-S1P antibody, LT1002, hasdemonstrated modulation of lymphocyte levels in mouse. This datasuggests that LT1002 could be a potentially beneficial therapeutic forauto-immune diseases and may provide a novel immunotherapeutic strategyfor the treatment of MS.

Other conditions characterized by an aberrant, excessive or undesiredimmune response

Methods of the present invention are also believed to be useful intreating conditions or diseases, other than autoimmune conditions, inwhich it is desirable to decrease or attenuate the immune response. Suchconditions may be characterized by an immune response which isexcessive, aberrant or undesired. Non-limiting examples includeallograft rejection and graft-versus-host disease. Allografting istransplantation of an organ or tissue (e.g., kidney, heart, lung,cornea, skin, bone marrow, pancreas or other tissues or organs) into agenetically non-identical member of the same species. Thus, most humanorgan and tissue transplants are allografts (with the majority of theremainder being transplants from an identical twin). Allograft rejectionoccurs when the transplant recipient's immune system recognizes theallograft as foreign and begins to destroy it. This may eventuallydestroy the transplanted organ and may result in the need for a secondtransplant. Thus, while not necessarily unexpected, allograft rejectionis an example of an immune response that is undesired.

Graft-versus-host disease (GVHD) is a complication of bone marrowtransplantation and stem cell transplant. Following a bone marrow orstem cell allograft, the transplanted donor cells, e.g., T cells, mayattack the patient's (the host's) body. GVHD may be chronic or acute,and may be life-threatening if uncontrolled. Thus, GVHD is an example ofan undesired and/or aberrant immune response.

Lymphocyte infiltration occurs in many diseases and conditions includingcancers, vascular injury, spinal cord injury, allergy and asthma.Schottenfeld and Beebe-Dimmer (2006) CA 56: 69. Zhu et al. (2002)Arteriosclerosis, Thrombosis Vasc Biol. 22: 450; (2002) Jones et al.(2002) J. Neurosci. 22: 2690; Gaga et al., (1991) J Immunol. 147:816-22;Boushey H A and J V Fahy (1995) Environ Health Perspect. 103 Suppl6:229-233. Disorders characterized by inappropriate or aberrantlymphocyte infiltration are also considered to be diseases characterizedby an excessive, aberrant or undesired immune response and therefore maybe treated according to the methods of the present invention.

In certain hematological cancers, such as multiple myeloma, a malignancyof B-cells and plasma cells, treatment often involves both anti-cancer(e.g., cytotoxic) agents and immunosuppressants such as dexamethasone toreduce the aberrant immune response, (i.e., B-cell proliferation). Amonoclonal antibody that binds S1P with high affinity and specificityhas been shown to slow tumor progression and associated angiogenesis inseveral animal models of human cancer. Visentin et al., (2006) CancerCell 9: 225-238. The applicants believe that the anti-S I P antibodycould be effective as an anti-cancer agent by virtue not only of itsanti-tumorigenic activity, but also because it may be immunosuppressant.It is believed to be particularly useful for treatment of multiplemyeloma and other hematological malignancies characterized by anaberrant or unwanted involvement, infiltration or proliferation oflymphocytes and their products.

Anti-S1P Antibodies for the Treatment of Scleroderma

The compositions and methods of the invention will be useful in treatingdisorders and diseases characterized, at least in part, by aberrantneovascularization, angiogenesis, fibrogenesis, fibrosis, scarring,inflammation, and immune response. One such disease is scleroderma,which is also referred to as systemic sclerosis.

Scleroderma is an autoimmune disease that causes scarring or thickeningof the skin, and sometimes involves other areas of the body, includingthe lungs, heart, and/or kidneys. Scleroderma is characterized by theformation of scar tissue (fibrosis) in the skin and organs of the body,which can lead to thickening and firmness of involved areas, withconsequent reduction in function. Today, about 300,000 Americans havescleroderma, according to the Scleroderma Foundation. One-third or lessof those affected have widespread disease, while the remainingtwo-thirds primarily have skin symptoms. When the disease affects thelungs and causing scarring, breathing can become restricted because thelungs can no longer expand as they should. To measure breathingcapability, doctors use a device that assesses forced vital capacity(FVC). In people with an FVC of less than 50 percent of the expectedreading, the 10-year mortality rate from scleroderma-related lungdisease is about 42 percent. One reason the mortality rate is so high isthat no effective treatment is currently available.

As described in the examples of this application, existing evidenceindicates that S1P is a pro-fibrotic growth factor that can contributeto fibroblast activation, proliferation, and the resulting increasedfibroblast activity associated with maladaptive scarring and remodeling.Moreover, potential roles for S1P in activity of skin and other types offibroblasts have been demonstrated. For example, it has been shown thatbioactive lipids stimulate the migration of murine skin fibroblasts(Hama, et al., J Biol Chem. Apr. 23, 2004;279(17):17634-9), and humanskin fibroblasts express several S1P receptor subtypes (Zhang, et al.,Blood. May 1, 1999;93(9):2984-90). In addition to the many directeffects of S1P on fibroblast activity, S1P also may have many potentialindirect effects on fibroblast activity. For example, S1P may facilitatethe action of other well-known pro-fibrotic factors, such as TGF-β andplatelet derived growth factor (PDGF). TGF-β is one of the most widelystudied and recognized contributors to fibrosis (Desmouliere, et al., JCell Biol 122: 103-111, 1993). TGF-βupregulates SphK1 expression andactivity leading to increased expression of tissue inhibitors ofmetalloproteinases 1 (TIMP-1), a protein that inhibits ECM degradation(Yamanaka, et al., J Biol Chem 279: 53994-54001, 2004). Increasedexpression of TIMP-1 is linked to interstitial fibrosis and diastolicdysfunction in heart failure patients (Heymans, et al., Am J Pathol 166:15-25, 2005). Conversely, S1P stimulates expression and release of TGF-β(Norata, et al., Circulation 111: 2805-2811, 2005). There is alsodistinct evidence of crosstalk between S1P and PDGF. S1P directlystimulates expression of PDGF (Usui, et al., J Biol Chem 279:12300-12311, 2004). In addition, the S1P₁ receptor and the PDGF receptorbind one another and their association is necessary for PDGF activationof downstream signaling which contributes to proliferation and migrationof various cell types (Long, et al., Prostaglandins Other Lipid Mediat80: 74-80, 2006; Baudhuin et al., Faseb J 18: 341-343, 2004). As such,the effects of TGF-β and PDGF on fibrosis may be due in part tocrosstalk with the S1P signaling pathway. As such, the compositions andmethods of the invention can be used to treat scleroderma, particularlyby decreasing the effective in vivo concentration of a particular targetlipid, for example, S1P.

Systemic scleroderma is thought to be exacerbated by stimulatoryautoantibodies against PDGF receptors (Baroni, et al., N Engl J Med.2006 v354(25):2667-76), and PDGF receptors are up-regulated inscleroderma fibroblasts in response to TGF-β (Yamakage, et al., J ExpMed. May 1, 1992;175(5):1227-34). Because of the substantial cross-talkamong the S1P, PDGF and TGF-β signaling systems, blocking S1Pbioactivity with and anti-S1P agent (e.g., an anti-S1P mAb) couldindirectly mitigate the pro-sclerotic effects of PDGF and TGF-β.Moreover, treatment with such an anti-S1P agent could benefitscleroderma patients by mitigating the direct effects of S1P on skin andother forms of fibroblasts that contribute to disease progression.

S1P and Ocular Diseases and Conditions

Pathologic or aberrant angiogenesis/neovascularization, aberrantremodeling, fibrosis and scarring and inflammation occur in associationwith retinal and ocular diseases such as age-related maculardegeneration (AMD), diabetic retinopathy (DR), and in retinopathy ofprematurity (ROP) and other developmental disorders [Eichler, et al.(2006), Curr Pharm Des, vol 12: 2645-60], as well as being a result ofinfections and mechanical injury to the eye [Ciulla, et al. (2001), CurrOpin Ophthalmol, vol 12: 442-9 and Dart et al (2003), Eye, vol 17:886-92]. It is believed that antibodies against S1P will be useful intreating ocular diseases for which pathologic or aberrantangiogenesis/neovascularization, aberrant remodeling, fibrosis, andscarring or inflammation are a component.

Angiogenesis/Neovascularization of the Eye:

Pathologic ocular angiogenesis is a leading cause of blindness in avariety of clinical conditions. Choroidal neovascularization (CNV)occurs in a number of ocular diseases, the most prevalent of which isthe exudative or “wet” form of AMD. As a result of an increasingly agedpopulation, AMD is a modern day epidemic and the leading cause ofblindness in the western world in patients over age 60. Despite theepidemic of vision loss caused by AMD, only a few therapies, mostlyanti-VEGF based, can slow the progression of AMD and even fewer canreverse vision loss [Bylsma and Guymer (2005), Clin Exp Optom,. vol 88:322-34, Gryziewicz (2005), Adv Drug Deliv Rev, vol 57: 2092-8, and Liuand Regillo (2004), Curr Opin Ophthalmol, vol 15: 221-6.]. Therefore,discovering new treatments for pathologic neovascularization isextremely important.

AMD is used here solely for illustrative purposes in describing ocularconditions relating to aberrant angiogenesis/neovascularization,aberrant remodeling, fibrosis and scarring, and inflammation, whichconditions are found in other ocular diseases and disorders as disclosedand claimed herein. AMD involves age-related pathologic changes [Tezel,Bora, and Kaplan (2004), Trends Mol Med, vol 10: 417-20 and Zarbin(2004), Arch Ophthalmol, 122: 598-614]. Multiple theories exist but, theexact etiology and pathogenesis of AMD are still not well understood.Aging is associated with cumulative oxidative injury, thickening ofBruch's membrane and drusen formation. Oxidative stress results ininjury to retinal pigment epithelial (RPE) cells and, in some cases, thechoriocapillaris [Zarbin (2004), Arch Ophthalmol, vol 122: 598-614, andGorin, et al. (1999), Mol Vis,. vol 5: 29]. Injury to RPE likely elicitsa chronic inflammatory response within Bruchs membrane and the choroid[Johnson et al. (2000), Exp Eye Res,. vol 70: 441-9]. This injury andinflammation fosters and potentates retinal damage by stimulating CNVand atrophy [Zarbin (2004), Arch Ophthalmol, vol 122: 598-614, andWitmer, et al. (2003), Prog Retin Eye Res, vol 22: 1-29]. CNV results indefective and leaky blood vessels (BV) that are likely to be recognizedas a wound [Kent and Sheridan (2003), Mol Vis, vol 9: 747-55]. Woundhealing arises from the choroid and invades the subretinal space throughBruchs membrane and the RPE. Wound healing responses are characterizedby a typical early inflammation response, a prominent angiogenicresponse and tissue formation followed by end-stage maturation of allinvolved elements. Wound remodeling may irreversibly compromisephotoreceptors and RPEs thereby, justifying the need to treat CNV withmore than anti-angiogenic therapies [La Cour, Kiilgaard, and Nissen(2002), Drugs Aging, vol 19: 101-33.12].

Alterations in the normal retinal and sub-retinal architecture as aresult of CNV related fibrosis, edema and inflammation individually orcumulatively, leads to AMD related visual loss [Tezel and Kaplan (2004),Trends Mol Med, vol 10: 417-20, and Ambati, et al. (2003), SurvOphthalmol, vol 48: 257-93]. The multiple cellular and cytokineinteractions which are associated with exudative AMD greatly complicatethe search for effective treatments. While CNV and edema are manageablein part by anti-VEGF therapeutics, potential treatments to mitigate scarformation and inflammation have not been adequately addressed [Bylsmaand Guymer (2005), Clin Exp Optom, vol 88: 322-34, and Pauleikhoff(2005), Retina, vol 25: 1065-84]. As long as the neovascular complexremains intact, as appears to be the case in patients treated withanti-VEGF agents, the potential for subretinal fibrosis and futurevision loss persists.

Anti-VEGF-A therapies represent a recent, significant advance in thetreatment of exudative AMD. However, the phase III VISION Trial withPEGAPTANIB, a high affinity aptamer which selectively inhibits the 165isoform of VEGF-A, demonstrated that the average patient continues tolose vision and only a small percent gained vision [Gragoudas, et al.(2004), N Engl J Med, vol 351: 2805-16]. Inhibition of all isoforms ofVEGF-A (pan-VEGF inhibition) with the antibody fragment RANIBIZUMAByielded much more impressive results [Brown, et al., N Eng Med (2006),vol. 355:1432-44, Rosenfeld, et al. N Eng J Med (2006), vol.355:1419-31]. The 2 year MARINA trial and the 1 year ANCHOR trialdemonstrated that approximately 40% of patients achieve some visualgain. Although these results represent a major advance in our ability totreat exudative AMD, they also demonstrate that 60% of patients do nothave visual improvement. Furthermore, these patients had to meetstrictly defined inclusion and exclusion criteria. The results in alarger patient population may be less robust.

There is still a well-defined need to develop further therapeutic agentsthat target other steps in the development of CNV and the processes thatultimately lead to photoreceptor destruction. First, the growth ofchoroidal BVs involves an orchestrated interaction among many mediators,not just VEGF, offering an opportunity to modulate or inhibit the entireprocess [Gragoudas, et al. (2004), N Engl J Med, vol 351: 2805-16].Second, exudative AMD is comprised of vascular and extravascularcomponents. The vascular component involves vascular endothelial cells(EC), EC precursors and pericytes. The extravascular component, whichvolumetrically appears to be the largest component, is composed ofinflammatory, glial, and retinal pigment epithelium (RPE) cells andfibroblasts. Tissue damage can result from either component. These otheraspects of the pathologic process are not addressed by current anti-VEGFtreatments. Targeting additional elements of the angiogenic cascadeassociated with AMD could provide a more effective and synergisticapproach to therapy [Spaide, R F (2006), Am J Ophthalmol, vol 141:149-156].

Inflammation in Ocular Disease:

There is increasing evidence that inflammation, specifically macrophagesand the complement system [Klein, et al. (2005), Science, vol 308:385-9; and Hageman, et al.(2005), Proc Natl Acad Sci U S A, vol 102:7227-32], plays an important role in the pathogenesis of exudative AMD.Histopathology of surgically excised choroidal neovascular membranesdemonstrates that macrophages are almost universally present[Grossniklaus, et al. (1994), Ophthalmology, vol 101: 1099-111, andGrossniklaus, et al. (2002), Mol Vis, vol 8: 119-26]. There is mountingevidence that macrophages may play an active role in mediating CNVformation and propagation [Grossniklaus, et al. (2003), Mol Vis, vol 8:119-26; Espinosa-Heidmann, et al (2003), Invest Ophthalmol Vis Sci, vol44: 3586-92; Oh, et al. (1999), Invest Ophthalmol Vis Sci, vol 40:1891-8; Cousins, et al. (2004), Arch Ophthalmol, vol 122: 1013-8;Forrester (2003), Nat Med, vol 9: 1350-1, and Tsutsumi, et al. (2003), JLeukoc Biol, vol 74: 25-32] by multiple effects which include secretionof enzymes that can damage cells and degrade Bruchs membrane as well asrelease pro-angiogenic cytokines [Otani, et al. (1999), Ophthalmol VisSci, vol 40: 1912-20, and Amin, Puklin, and Frank (1994), InvestOphthalmol Vis Sci, vol 35: 3178-88]. At the site of injury, macrophagesexhibit micro-morphological signs of activation, such as degranulation[Oh, et al. (1999), Invest Ophthalmol Vis Sci, vol 40: 1891-8, andTrautmann et al. (2000), J Pathol, vol 190: 100-6]. Thus it is believedthat a molecule which limited macrophage infiltration into to thechoroidal neovascular complex may help limit CNV formation.

Choroidal Neovascularization and Blood Vessel Maturation in OcularDisease:

Angiogenesis is an essential component of normal wound healing as itdelivers oxygen and nutrients to inflammatory cells and assists indebris removal [Lingen (2001), Arch Pathol Lab Med, vol 125: 67-71].Progressive angiogenesis is composed of two distinct processes: Stage I:Migration of vascular ECs, in response to nearby stimuli, to the tips ofthe capillaries where they proliferate and form luminal structures; andStage II: Pruning of the vessel network and optimization of thevasculature [Guo, et al. (2003), Am J Pathol, vol 162: 1083-93].

Stage I: Neovascularization. Angiogenesis most often aids wound healing.However, new vessels, when uncontrolled, are commonly defective andpromote leakage, hemorrhaging, and inflammation. Diminishingdysfunctional and leaky BVs, by targeting pro-angiogenic GFs, hasdemonstrated some ability to slow the progression of AMD [Pauleikhoff(2005), Retina, vol 25: 1065-84.14, and van Wijngaarden, Coster, andWilliams (2005), JAMA, vol 293: 1509-13].

Stage II: Blood vessel maturation and drug desensitization. Pan-VEGFinhibition appears to exert its beneficial effect mostly via ananti-permeability action resulting in resolution of intra- andsub-retinal edema, as the actual CNV lesion does not markedly involute.The lack of marked CNV involution may in part be a result of maturationof the newly formed vessels due to pericyte coverage. Pericytes play acritical role in the development and maintenance of vascular tissue. Thepresence of pericytes seems to confer a resistance to anti-VEGF agentsand compromise their ability to inhibit angiogenesis [Bergers and Song(2005), Neuro-oncol, vol 7: 452-64; Yamagishi and Imaizumi (2005), Int JTissue React, vol 27: 125-35; Armulik, Abramsson and Betsholtz (2005),Circ Res, vol 97: 512-23; Ishibashi et al. (1995), Arch Ophthalmol, vol113: 227-31] . An agent that has an inhibitory effect on pericyterecruitment would likely disrupt vascular channel assembly and thematuration of the choroidal neovascular channels thereby perpetuatingtheir sensitivity to anti-angiogenic agents.

Remodeling of the vascular network involves adjustments in blood vessel(BV) density to meet nutritional needs [Gariano and Gardner (2005),Nature, 438: 960-6]. Periods of BV immaturity corresponds to a period inwhich new vessels are functioning but have not yet acquired a pericytecoating [Benjamin, Hemo, and Keshet (1998), Development, 125: 1591-8,and Gerhardt and Betsholtz (2003), Cell Tissue Res, 2003. 314: 15-23].This delay is essential in providing a window of plasticity for the finetuning of the developing vasculature according to the nutritional needsof the retina or choroid.

The bioactive lipid sphingosine-1-phosphate (S1P), VEGF, PDGF,angiopoietins (Ang) and other growth factors (GF) augment blood vesselgrowth and recruit smooth muscle cells (SMC) and pericytes to naivevessels which promote the remodeling of emerging vessels [Allende andProia (2002), Biochim Biophys Acta, vol 582: 222-7; Gariano and Gardner(2005), Nature, vol 438: 960-6; Grosskreutz, et al. (1999), MicrovascRes, vol 58: 128-36; Nishishita, and Lin (2004), J Cell Biochem, vol 91:584-93, and Erber, et al (2004), FASEB J, vol 18: 338-40.32]. Pericytes,most likely generated by in situ differentiation of mesenchymalprecursors at the time of EC sprouting or from the migration andde-differentiation of arterial smooth muscle cells, intimately associateand ensheath ECs resulting in overall vascular maturity and survival[Benjamin, Hemo, and Keshet (1998), Development, vol 125: 1591-8].Recent studies have demonstrated that S1P, and the S1P 1 receptor, areinvolved in cell-surface trafficking and activation of the cell-celladhesion molecule N-cadherin [Paik, et al. (2004), Genes Dev, vol 18:2392-403]. N-cadherin is essential for interactions between EC,pericytes and mural cells which promote the development of a stablevascular bed [Gerhardt and Betsholtz (2003), Cell Tissue Res, vol 314:15-23]. Global deletion of the S1P 1 gene results in aberrant mural cellensheathment of nascent BVs required for BV stabilization duringembryonic development [Allende and Proia (2002), Biochim Biophys Acta,vol 1582: 222-7]. Local injection of siRNA to S1P1 suppresses vascularstabilization in tumor xenograft models [Chae, et al. (2004), J ClinInvest, vol 114: 1082-9]. Transgenic mouse studies have demonstratedthat VEGF and PDGF-B promote the maturation and stabilization of new BVs[Guo, et al. (2003), Am J Pathol, 162: 1083-93, and Gariano and Gardner(2005), Nature, vol 438: 960-6.50]. VEGF up-regulates Ang-1 (mRNA andprotein) [Asahara, et al. (1998), Circ Res, vol 83: 233-40]. Ang-1 playsa major role in recruiting and sustaining peri-endothelial support bypericytes [Asahara, et al. (1998), Circ Res, vol 83: 233-40].Intraocular injection of VEGF accelerated pericyte coverage of the ECplexus [Benjamin, Hemo, and Keshet (1998), Development, vol 125:1591-8]. PDGF-B deficient mouse embryos lack micro-vascular pericytes,which leads to edema, micro-aneurisms and lethal hemorrhages [Lindahl,et al. (1997), Science, vol 277: 242-5]. Murine pre-natal studies havedemonstrated that additional signals are required for complete VEGF- andPDGF-stimulation of vascular bed maturation. Based upon thetrans-activation of S1P noted above, this factor could be S1P [Erber etal. (2004), FASEB J, vol 18: 338-40]. Vessel stabilization andmaturation is associated with a loss of plasticity and the absence ofregression to VEGF and other GF withdrawal and resistance toanti-angiogenic therapies [Erber, et al. (2004), FASEB J, vol 18:338-40, and Hughes and Chan-Ling (2004), Invest Ophthalmol Vis Sci, vol45: 2795-806]. Resistance of BVs to angiogenic inhibitors is conferredby pericytes that initially stabilize matured vessels and those that arerecruited to immature vessels upon therapy [Erber, et al (2004), FASEBJ, vol 18: 338-40]. After ensheathment of the immature ECs, thepericytes express compensatory survival factors (Ang-1 and PDGF-B) thatprotect ECs from pro-apoptotic agents.

Edema and Vascular Permeability in Ocular Disease:

CNV membranes are composed of fenestrated vascular ECs that tend to leaktheir intravascular contents into the surrounding space resulting insubretinal hemorrhage, exudates and fluid accumulation [Gerhardt andBetsholtz (2003), Cell Tissue Res, vol 14: 15-23]. For many years theCNV tissue itself, and more recently intra-retinal neovascularization,have been implicated as being responsible for the decrease in visualacuity associated with AMD. It is now thought however, that macularedema caused by an increase in vascular permeability (VP) and subsequentbreakdown of the blood retinal barrier (BRB), plays a major role invision loss associated with AMD and other ocular diseases, includingblindness associated with diabetes. [Hughes and Chan-Ling (2004), InvestOphthalmol Vis Sci, vol 45: 2795-806; Felinski and Antonetti (2005),Curr Eye Res, vol 30: 949-57; Joussen, et al. (2003), FASEB J, vol 17:76-8, and Strom, et al (2005), Invest Ophthalmol Vis Sci, vol 46:3855-8]. In particular, diabetic retinopathy (DR) and diabetic macularedema (DME) are common microvascular complications in patients withdiabetes and are the most common causes of diabetes-associatedblindness. DME results from increased microvascular permeability.Joussen, et al. (2003), FASEB J, vol 17: 76-8. Together these are themost common cause of new blindness in the working-age population. It isbelieved that compounds, such as antibodies that target S1P, will betherapeutically useful for these conditions.

Examples of several classes of ocular diseases that may be treated inaccordance with the invention are described below. It will beappreciated that many disease and conditions are characterized, at leastin part, by multiple pathological processes (for example, bothpathological neovascularization and scarring) and that theclassifications provided herein are for descriptive convenience and donot limit the invention.

a. Ischemic Retinopathies Associated with Pathologic Neovascularizationand Diseases Characterized by Epiretinal and or Subretinal MembraneFormation.

Ischemic retinopathies (IR) are a diverse group of disorderscharacterized by a compromised retinal blood flow. Examples of IRinclude diabetic retinopathy (DR), retinopathy of prematurity (ROP),sickle cell retinopathy and retinal venous occlusive disease. All ofthese disorders can be associated with a VEGF driven proliferation ofpathological retinal neovascularization which can ultimately lead tointraocular hemorrhaging, epi-retinal membrane formation and tractionalretinal detachment. Idiopathic epi-retinal membranes (ERMs), also calledmacular pucker or cellophane retinopathy, can cause a reduction invision secondary to distortion of the retinal architecture. Thesemembranes sometimes recur despite surgical removal and are sometimesassociated with retinal ischemia. VEGF and its receptors are localizedto ERMs. The presence of VEGF in membranes associated with proliferativediabetic retinopathy, proliferative vitreoretinopathy, and macularpucker further suggests that this cytokine plays an important role inangiogenesis in ischemic retinal disease and in membrane growth inproliferative vitreoretinal disorders. In addition, VEGF receptorsVEGFR1 and VEGFR2 are also identified on cells in ERMs. These data showthat VEGF may be an autocrine and/or paracrine stimulator that maycontribute to the progression of vascular and avascular ERMs. PDGF andits receptors [Robbins, et al. (1994), Invest Ophthalmol Vis Sci; vol35: 3649-3663] has been described in eyes with proliferative retinaldiseases [Cassidy, et al. (1998), Br J Ophthamol; vol 82: 181-85, andFreyberger, et al. (2000), Exp Clin Endocrinol Diabetes, vol 108:106-109]. These findings suggest that PDGF ligands and receptors arewidespread in proliferative retinal membranes of different origin andsuggest that autocrine and paracrine stimulation with PDGF may beinvolved in ERM pathogenesis. Transforming growth factor-β (TGF-β) isinvolved in the formation of ERMs [Poumaras, et al. (1998), KlinMonatsbl Augenheilkd, vol 212: 356-358] as demonstrated by TGF stainingand immunoreactivity. In addition, TGF-β receptor II is expressed inmyofibroblasts of ERM of diabetic and PVR membranes. These resultssuggest that TGF-β, produced in multiple cell types in retina and ERMs,is an attractive target for the treatment of PVR, diabetic and secondaryERMs. Interleukin-6 (IL-6) has been reported to be increased in humanvitreous in proliferative diabetic retinopathy (PDR) [La Heij, et al.(2002), Am J Ophthal, 134: 367-375] and in one study 100% of thediabetic ERMs studied expressed IL-6 protein [Yamamoto, et al. (2001) AmJ Ophthal, vol 132: 369-377].

Exogenous administration of basic fibroblastic growth factor (bFGF) hasbeen shown to induce endothelial proliferation and VEGF expression[Stavri, et al. (1995), Circulation, vol 92: 11-14]. Consistent withthese observations, bFGF concentration is increased in vitreous samplesfrom patients with PDR [Sivalingam, et al. (1990), Arch Ophthalmol, vol108: 869-872, and Boulton, et al. (1997), Br J Ophthalmol, vol 81:228-233]. bFGF is also involved in the formation of ERMs [Hueber, et al.(1996), Int. Ophthalmol, vol 20: 345-350] demonstrated bFGF in 8 out of10 PDR membranes studied. Moreover, these workers found positivestaining for the corresponding receptor, FGFR1. Immunoreactivity forbFGF has also been demonstrated in nonvascular idiopathic ERMs. Theseresults implicate bFGF in the formation of both vascular and avascularERMs. Harada, et al. (2006), Prog in Retinal and Eye Res, vol 25;149-164. Elevated bFGF has also been detected in the serum of patientswith ROP (Becerril, et al. (2005), Ophthalmology, vol 112, 2238].

Given the known pleotropic effects of S1P and its interactions withVEGF, bFGF, PDGF, TGF-β and IL-6, it is believed that an agent thatbinds, antagonizes, inhibits the effects or the production of S1P willbe effective at suppressing pathologic retinal neovascularization inischemic retinopathies and posterior segment diseases characterized byvascular or avascular ERM formation. Other ocular conditionscharacterized, at least in part, by aberrant neovascularization orangiogenesis include age-related macular degeneration, corneal graftrejection, neovascular glaucoma, contact lens overwear, infections ofthe cornea, including herpes simplex, herpes zoster and protozoaninfection, pterygium, infectious uveitis, chronic retinal detachment,laser injury, sickle cell retinopathy, venous occlusive disease,choroidal neovascularization, retinal angiomatous proliferation, andidiopathic polypoidal choroidal vasculopathy.

b. Proliferative Vitreoretinopathy (PVR).

PVR is observed after spontaneous rhegmatogenous retinal detachment andafter traumatic retinal detachment. It is a major cause of failedretinal detachment surgery. It is characterized by the growth andcontraction of cellular membranes on both sides of the retina, on theposterior vitreous surface and the vitreous base. This excessive scartissue development in the eye may lead to the development of tractionalretinal detachment, and therefore treatments directed at the preventionor inhibition of proliferative vitreoretinopathy (PVR) are a logicalprinciple of management of retinal detachment. Histopathologically PVRis characterized by excessive collagen production, contraction andcellular proliferation [Michels, Retinal Detachment 2nd Edition.Wilkinsin C P, Rice T A Eds, Complicated types of retinal detachment, pp641-771, Mosby St Louis 1997]. Cellular types identified in PVRmembranes include mainly retinal pigmented epithelial cells,fibroblasts, macrophages and vascular endothelial cells [Jerdan, et al.(1989), Ophthalmology, vol 96: 801-10, and Vidinova, et al. (2005), KlinMonatsbl Augenheilkd; vol 222:568-571]. The pathophysiology of thisexcessive scarring reaction appears to be mediated by a number ofcytokines including platelet derived growth factor (PDGF), transforminggrowth factor (TGF) beta, basic fibroblastic growth factor (bFGF),interleukin-6 (IL)-6, and interleukin-8 (IL)-8 [Nagineni, et al. (2005),J Cell Physiol, vol 203: 35-43; La Heij, et al (2002), Am J Ophthalmol,134: 367-75; Planck, et al. (1992), Curr Eye Res; vol 11: 1031-9;Canataroglu et al. (2005) Ocul Immunol Inflamm; vol 13: 375-81, andAndrews, et al. (1999), Ophthalmol Vis Sci; vol 40: 2683-9]. Inhibitionof these cytokines may help prevent the development of PVR if given in atimely fashion or limit its severity [Akiyama, et al (2006), J CellPhysiol, vol 207:407-12, and Zheng, et al (2003), Jpn J Ophthalmolm, vol47:158-65].

Sphingosine-1-Phosphate (S1P) is a bioactive lysolipid with pleotrophiceffects. It is pro-angiogenic, pro inflammatory (stimulates therecruitment of macrophages and mast cells) and pro-fibrotic (stimulatesscar formation). S1P generally stimulates cells to proliferate andmigrate and is anti-apoptotic. S1P achieves these biologically diversefunctions through its interactions with numerous cytokines and growthfactors. Inhibition of S1P via a monoclonal antibody (SPHINGOMAB) hasbeen demonstrated to block the functions of vascular endothelial growthfactor (VEGF), bFGF, IL-6, and IL-8 [Visentin, B et al. (2006), CancerCell, vol 9: 1-14]. Binding of S1P to the S1P₁ receptor can alsoincrease PDGF production; therefore an agent that binds S1P would alsobe expected to diminish PDGF production [Milstien and Spiegel (2006),Cancer Cell, vol 9:148-150]. As shown in the Examples below, it has nowbeen demonstrated that in vitro S1P transforms human RPE cells into amyofibroblast-like phenotype similar to the type seen in PVR. Given thepathophysiology that ultimately results in the excessive scarring seenin PVR and the known effects of S1P on these same key mediators, it isbelieved that an agent that binds, antagonizes, or inhibits the effectsor the production of S1P will be effective at eliminating or minimizingthe development of PVR and its severely damaging effects on the eye.

c. Uveitis.

Uveitis is an inflammatory disorder of the uveal tract of the eye. Itcan affect the front (anterior) or back (posterior) of the eye or both.It can be idiopathic or infectious in etiology and can bevision-threatening. Idiopathic uveitis has been associated withincreased CD4+ expression in the anterior chamber [Calder, et al.(1999), Invest Ophthalmol Vis Sci, vol 40: 2019-24]. Data also suggestsa pathologic role of the T lymphocyte and its chemoattractant IP-10 inthe pathogenesis of uveitis [Abu El-Asrar (2004), Am J Ophthalmol, vol138: 401-11]. Other chemokines in acute anterior uveitis includemacrophage inflammatory proteins, monocyte chemoattractant protein-1 andIL-8. These cytokines probably play a critical role in leukocyterecruitment in acute anterior uveitis. Verma, et al. (1997), Curr EyeRes; vol 16; 1202-8. Given the profound and pleiotropic effects of theS1P signaling cascade, it is believed that SPHINGOMAB and other immunemoieties that reduce the effective concentration of bioactive lipidwould serve as an effective method of reducing or modulating theintraocular inflammation associated with uveitis.

d. Refractive Surgery.

The corneal wound healing response is of particular relevance forrefractive surgical procedures since it is a major determinant of safetyand efficacy. These procedures are performed for the treatment ofmyopia, hyperopia and astigmatism. Laser in situ keratomileusis (LASIK)and photorefractive keratectomy (PRK) are the most common refractiveprocedures however others have been developed in an attempt to overcomecomplications. These complications include overcorrection,undercorrection, regression and stromal opacification among others. Anumber of common complications are related to the healing response andhave their roots in the biologic response to surgery. One of thegreatest challenges in corneal biology is to promote tissue repair viaregeneration rather than fibrosis. It is believed that the choicebetween regeneration and fibrosis lies in the control of fibroblastactivation [Stramer, et al (2003), Invest Ophthalmol Vis Sci; vol 44:4237-4246, and Fini (1999) Prog Retin Eye Res, vol 18: 529-551]. Cellscalled myofibroblasts may appear in the subepithelial stroma 1-2 weeksafter surgery or injury. Myofibroblasts are presumably derived fromkeratocytes under the influence of TGF-β [Jester, et al. (2003), Exp EyeRes, vol 77: 581-592]. Corneal haze and stromal scarring arecharacterized by reduced corneal transparency and may be associated withfibroblast and myofibroblast generation. In situ and in vitro studieshave suggested that TGF-β and PDGF are important in stimulatingmyofibroblast differentiation [Folger, et al. (2001), Invest OphthalmolVis Sci; 42: 2534-2541]. Haze can be noted in the central interfaceafter LASIK under certain circumstances. These include diffuse lamellarkeratitis, donut-shaped flaps, and retention of epithelial debris at theinterface. It is likely that each of these is associated with increasedaccess of TGF-β from epithelial cells to the activated keratocytes[Netto, et al. (2005), Cornea, vol 24: 509-522]. Regression is mostlikely due to heightened epithelial-stromal wound healing interactionssuch as increased production of epithelium modulating growth factors bycorneal fibroblasts and or myofibroblasts [Netto, et al. (2005), above].Inhibition of TGF-β binding to receptors with topical anti-TGF-βantibody has been shown to reduce haze induced by PRK [Jester, et al.(1997), Cornea, vol 16: 177-187]. Given the known effects ofanti-bioactive lipid antibody on the fibrotic process and TGF-β, webelieve that it may aid in treating some of the complications ofrefractive surgery such as haze, stromal scarring and regression.

e. Modulation of Glaucoma Filtration Surgery.

Glaucoma is classically thought of a disease whereby elevatedintraocular pressure causes damage to the optic nerve and ultimatelycompromises the visual field and or the visual acuity. Other forms ofglaucoma exist where optic nerve damage can occur in the setting ofnormal pressure or so called “normal tension glaucoma”. For manypatients medications are able to control their disease, but for othersglaucoma filtration surgery is needed whereby a fistula is surgicallycreated in the eye to allow fluid to drain. This can be accomplished viatrabeculectomy, the implantation of a medical device or other methods ofsurgical intervention. Glaucoma filtration surgery fails due to a woundhealing process characterized by the proliferation of fibroblasts andultimately scarring. Anti-metabolites such as 5-fluorouracil andmitomycin C can reduce subsequent scarring; however, even with the useof these drugs long term follow up shows that surgical failure is stilla serious clinical problem [Mutsch and Grehn (2000), Graefes Arch ClinExp Ophthalmol; vol 238: 884-91, and Fontana, et al. (2006),Ophthalmology, vol 113: 930-936]. Studies of human Tenon's capsulefibroblasts demonstrate that they have the capacity to synthesize bFGFand PDGF and TGF-β and that these growth factors are implicated in thetissue repair process after glaucoma filtration surgery that contributesto the failure of the procedure. Trpathi, et al. (1996), Exp Eye Res,vol 63: 339-46. Additional studies have also implicated these growthfactors in the post filtration wound response [Denk, et al. (2003), CurrEye Res; vol 27: 35-44] concluded that different isoforms of PDGF aremajor stimulators of proliferation of Tenon's capsule fibroblasts afterglaucoma filtration surgery while TGF-β is essential for thetransformation of Tenon's capsule fibroblasts into myofibroblasts. Wehave demonstrated that S1P is present in human Tenon'scapsule/conjunctival fibroblasts and that S1P is strongly expressed inthe wound healing response. S1P also stimulates the profibrotic functionof multiple fibroblast cell types and the transformation into themyofibroblast phenotype and collagen production. Given the specificpleotropic effects of S1P and its known interactions with bFGF, PDGF,and TGF-beta, it is believed that an agent that binds, antagonizes,inhibits the effects or the production of S1P will be effective atmodulating the wound healing and/or fibrotic response that leads tofailure of glaucoma surgery and will be an effective therapeutic methodof enhancing successful surgical outcomes. It is envisioned that theagent could be administered, e.g., via intravitreal or subconjunctivalinjection or topically.

f. Corneal Transplantation.

Corneal transplantation (penetrating keratoplasty (PK)) is the mostsuccessful tissue transplantation procedure in humans. Yet of the 47,000corneal transplants performed annually in the United States, cornealallograft rejection is still the leading cause of corneal graft failure[Ing, et al. (1998), Ophthalmology, vol 105: 1855-1865]. Currently,there is insufficient ability to avert allograft rejection althoughimmunosuppression and immunomodulation may be a promising approach.Recently it has been discovered that CD4(+) T cells function as directlyas effector cells and not helper cells in the rejection of cornealallografts. Hegde, et al. (2005), Transplantation, vol 79: 23-31. Murinestudies have shown increased numbers of neutrophils, macrophage and mastcells in the stroma of corneas undergoing rejection. Macrophages werethe main infiltrating cell type followed by T-cells, mast cells andneutrophils. The early chemokine expression in high risk cornealtransplantation was the mouse homologue of IL-8 (macrophage inflammatoryprotein-2) and monocyte chemotactic protein-1 (MCP-1) [Yamagami, et al.(2005), Mol Vis, vol 11, 632-40].

FTY720 (FTY) is a novel immunosuppressive drug that acts by alteringlymphocyte trafficking; resulting in peripheral blood lymphopenia andincreased lymphocyte counts in lymph nodes. FTY mediates itsimmune-modulating effects by binding to some of the S1P receptorsexpressed on lymphocytes [Bohler, et al. (2005), Transplantation, vol79: 492-5]. The drug is administered orally and a single oral dosereduced peripheral lymphocyte counts by 30-70%. FTY reduced T-cellsubset, CD4(+) cells more than CD8(+) cells. Bohler, et al. (2004),Nephrol Dial Transplant, vol 19: 702-13. FTY treated mice showed asignificant prolongation of orthotopic corneal-graft survival whenadministered orally. Zhang, et al. (2003), Transplantation, vol 76:1511-3. FTY oral treatment also significantly delayed rejection anddecreased its severity in a rat-to-mouse model of cornealxenotransplantation [Sedlakova, et al. (2005), Transplantation, vol 79,297-303]. Given the known pathogenesis of allograft rejection combinedwith the data suggesting that modulating the effects of the S1Psignaling can improve corneal graft survival, it is believed that immunemoieties that decrease the effective concentration of bioactive lipids,e.g., SPHINGOMAB, will also be useful in treatment of immunologicconditions such as allograft rejection, for example by attenuating theimmune response, and thus will likely improve corneal graft survivalafter PK. The drug may also has the added advantage that in addition tosystemic administration, local administration, e.g., via topicalperiocular or intraocular delivery, is possible.

Other ocular diseases with an inflammatory or immune component includechronic vitritis, infections, including herpes simplex, herpes zoster,and protozoan infections, and ocular histoplasmosis.

g. Anterior Segment Diseases Characterized by Scarring.

Treatment with an antibody targeted to bioactive lipid also is believedto benefit several conditions characterized by scarring of the anteriorportion of the eye. These include the following:

i. Trauma

The cornea, as the most anterior structure of the eye, is exposed tovarious hazards ranging from airborne debris to blunt trauma that canresult in mechanical trauma. The cornea and anterior surface of the eyecan also be exposed to other forms of trauma from surgery, and chemical,such as acid and alkali, injuries. The results of these types ofinjuries can be devastating often leading to corneal and conjunctivalscarring symblephera formation. In addition, corneal neovascularizationmay ensue. Neutrophils accumulate, their release of leukotrienes, andthe presence of interleukin-1 and interleukin-6, serves to recruitsuccessive waves of inflammatory cells [Sotozono, et al. (1997), CurrEye Res, vol 19: 670-676] that infiltrate the cornea and releaseproteolytic enzymes, which leads to further damage and break down ofcorneal tissue and a corneal melt. In addition, corneal and conjunctivalfibroblasts become activated and invade and leading to collagendeposition and fibrosis. The undesirable effects of excessiveinflammation and scarring are promoted by TGF-β. Saika, et al. (2006),Am J Pathol vol 168, 1848-60. This process leads to loss of cornealtransparency and impaired vision. Reduced inflammation, includingdecreased neutrophil infiltrates and reduced fibrosis resulted in fasterand more complete healing in a murine model of alkali burned corneas[Ueno, et al. (2005), Ophthalmol Vis Sci, vol 46: 4097-106].

ii. Ocular Cicatricial Pemphigoid (OCP)

OCP is a chronic cicatrizing (scar-forming) autoimmune disease thatprimarily affects the conjunctiva. The disease is invariably progressiveand the prognosis is quite poor. In its final stages conjunctivalscarring and the associated keratopathy lead to bilateral blindness.Histologically the conjunctiva shows submucosal scarring and chronicinflammation in which mast cell participation is surprisingly great[Yao, et al. (2003), Ocul Immunol Inflamm, vol 11: 211-222].Autoantigens lead to the formation of autoantibodies. The binding of theautoantibody to the autoantigen sets in motion a complex series ofevents with infiltration of T lymphocytes where CD4 (helper) cells faroutnumber CD8 (suppressor) cells. Macrophage and mast cell infiltrationalso ensue as well as the release of proinflammatory and profibroticcytokines. Cytokine-induced conjunctival fibroblast proliferation andactivation results, with resultant subepithelial fibrosis (see exampleshereinbelow). Studies have shown a role of TGF-β and IL-1 inconjunctival fibrosis in patients with OCP [Razzaque, et al. (2004),Invest Ophthalmol Vis Sci, vol 45: 1174-81].

iii. Stevens Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN)

SJS and TEN are life-threatening adverse reactions to medications. Theocular sequelae of these two related conditions can be severe andinvolve pathologic changes of the bulbar and palpebral conjunctiva,eyelids, and cornea. Drugs and infections are the most commonprecipitating factors. Chronic eye findings include scarring,symblepharon formation, and cicatrisation of the conjunctiva as a resultof the initial inflammatory process. This leads to entropion formation,trichiasis, and instability of the tear film. Breakdown of the ocularsurface leads to corneal scarring, neovascularization, and in severecases keratinization. As in OCP subepithelial fibrosis of theconjunctiva occurs. A vigorous autoimmune lymphocyte response to a drugor infection is believed to play a role in development of SJS/TEN.Harilaos, et al. (2005), Erythema Multiforme, Stevens Johnson Syndrome,and Toxic Epidermal Necrolysis, in Cornea 2^(nd) edition. Krachmer,Mannis, Holland eds. Elesevier Mosby Philadelphia. The infiltrating cellpopulation in SJS includes macrophages, CD4 positive T cells, and CD8positive T cells. This cell population is similar to those seen inchemical injury. Kawasaki, et al. (2000), J Ophthalmol, vol 84: 1191-3.

iv. Pterygium

Clinically a pterygium appears as a fleshy, vascular mass that occurs inthe interpalpebral fissure. The body of the pterygium is a fleshyfibrovascular mass. Active pterygium is characterized by marked vascularengorgement and progressive growth. They are firmly adherent to theglobe. In advanced cases the pterygium encroaches onto the cornea andmay cause visual loss secondary to loss of corneal transparency withinthe visual axis or irregular astigmatism. Symptomatically, patients mayexperience foreign body sensation, tearing and blurred vision.Histopathology demonstrates hyalinization of the subepithelialconnective tissue of the substantia propria, increased number offibroblasts and increased mast cells. Butrus, et al. (1995), Am JOphthalmol, vol 119: 236-237. Management of pterygium remainsproblematic. Surgical excision is often performed however recurrencerates are high [Krag, et al. (1992), Acta Ophthalmol, vol 70: 530]. Inorder to help lower the recurrence rate of pterygium, variouspharmacologic adjuvants have been employed such as Mitomycin-C anddaunorubicin. Although these may be helpful, long term data are limitedand they can be associated with scleral thinning and corneal melt.Dougherty, et al. [(1996), Cornea, vol 15: 537-540, and Lee, et al.(2001), Cornea, vol 20: 238-42] were the first to demonstrate that VEGFmay play an important role in the development of pterygium and toidentify VEGF and nitric oxide in the epithelium of pterygium. Theseworkers hypothesized that these as well as other cytokines areresponsible for the fibrovascular ingrowth characteristic of pterygium.The presence of basic FGF and TGF-beta 1 in both primary and recurrentpterygium has been demonstrated [Kira, et al. (1998), Graefes Arch ClinExp Ophthalmol, vol 236: 702-8] and published morphometric andimmunohistochemical evidence further supports the notion thatangiogenesis may play a role in the formation of pterygium [Marcovich,et al (2002), Curr Eye Res, vol 25:17-22]. Other studies have implicatedIL-6 and IL-8 as well as VEGF as mediators that may be relevant topterygium development [Di Girolamo, et al. (2006), Invest Ophthalmol VisSci, vol 47: 2430-7]. An effective agent against pterygium formation andgrowth may diminish the need for surgical intervention or reducerecurrence rates.

Other ocular diseases and conditions with a fibrogenesis, fibrosis orscarring component include AMD, diabetic retinopathy, retinopathy ofprematurity, sickle cell retinopathy, ischemic retinopathy, retinalvenous occlusive disease, and contact lens overwear.

In summary, excessive scarring is an underlying component of thepathophysiology of many ocular and non-ocular diseases and conditions.Bioactive lipids like S1P play a role in this process and anantibody-related treatment to diminish the concentrations of theseagents will likely lead to therapeutic benefit to patients receiving thetreatment. In one embodiment, inhibitors of bioactive lipids,particularly monoclonal antibodies directed against S1P and/or itvariants, are believed to be useful in modulating surgical and traumaticwound healing responses.

Fibrosis, Fibrogenesis and Scar Formation:

The formation of subretinal fibrosis leads to irreversible damage to thephotoreceptors and permanent vision loss. As long as the neovascularcomplex remains intact, as appears to be the case in patients treatedwith anti-VEGF agents, the potential for subretinal fibrosis and futurevision loss persists. In an update of the PRONTO study of RANIBIZUMAB(Lucentis®), it was discovered that those patients who lost vision didso as a result of either subretinal fibrosis or a RPE tear. An agentthat could diminish the degree of fibroblast infiltration and collagendeposition would be of value.

Fibroblasts, particularly myofibroblasts, are key cellular elements inscar formation in response to cellular injury and inflammation [Tomasek,et al. (2002), Nat Rev Mol Cell Biol, vol 3: 349-63, and Virag and Murry(2003), Am J Pathol, vol 163: 2433-40]. Collagen gene expression bymyofibroblasts is a hallmark of remodeling and necessary for scarformation [Sun and Weber (2000), Cardiovasc Res, vol 46: 250-6, and Sunand Weber (1996), J Mol Cell Cardiol, vol 28: 851-8]. S1P promotes woundhealing by activating fibroblast migration and proliferation whileincreasing collagen production [Sun, et al. (1994), J Biol Chem, vol269: 16512-7]. S1P produced locally by damaged cells could beresponsible for the maladaptive wound healing associated with remodelingand scar formation. Thus, it is believed that S1P inhibitors are usefulin diseases or conditions characterized, at least in part, by aberrantfibrogenesis or fibrosis.

The formation of subretinal fibrosis leads to irreversible damage to thephotoreceptors and permanent vision loss. As long as the neovascularcomplex remains intact, as appears to be the case in patients treatedwith anti-VEGF agents, the potential for subretinal fibrosis and futurevision loss persists.

Minimizing maladaptive scar formation by neutralization of S1P could bebeneficial and prevent irreversible losses in visual acuity by limitingthe extent of sub-retinal fibrosis and subsequent photoreceptor damage.Growing evidence suggests that S1P could contribute to both the earlyand late stages of maladaptive retinal remodeling associated withexudative AMD. S1P has a pronounced non-VEGF dependent pro-angiogeniceffect. S1P also stimulates migration, proliferation and survival ofmultiple cell types, including fibroblasts, EC, pericytes andinflammatory cells-the same cells that participate in the multiplemaladaptive processes of exudative AMD and other ocular disorders. S1Pis linked to the production and activation of VEGF, bFGF, PDGF, andother growth factors (GFs) implicated in the pathogenesis of exudativeAMD. Finally, S1P may modulate the maturation of naive vasculature, aprocess leading to a loss of sensitivity to anti-angiogenic agents.Inhibiting the action of S1P could be an effective therapeutic treatmentfor exudative AMD that may offer significant advantages over exclusivelyanti-VEGF approaches or may act synergistically with them to address thecomplex processes and multiple steps that ultimately lead to AMDassociated visual loss.

Currently favored therapeutic modalities for AMD include Lucentis® andoff-label use of Avastin® (Genentech, Inc.), both of which target asingle growth factor (VEGF-A) and appear to exert most of theirbeneficial effect via an anti-permeability action resulting inresolution of sub-retinal and intra-retinal edema, as the actualchoroidal neovascular (CNV) lesion does not markedly involute. However,exudative AMD-related vision loss is not solely due to CNV-inducedsub-retinal and intra-retinal edema. Pathologic disruption andremodeling of the retinal and subretinal architecture causedcollectively by CNV, sub-retinal fibrosis, edema and inflammationtogether result in the loss of visual acuity associated with AMD. Thesemultiple causes are not addressed by available treatments, includingLucentis™. Thus a therapeutic agent that could treat the multiplemechanisms that cause vision loss would be of great value, either asmonotherapy or in combination with another agent, such as an anti-VEGFagent (e.g., Lucentis® or Avastin°)

Thus, without wishing to be bound by any particular theory, it isbelieved that the level of undesirable sphingolipids such as S1P, and/orone or more of their metabolites, cause or contribute to the developmentof various ocular diseases and disorders where inappropriateinflammation, fibrosis and/or angiogenesis are involved in thepathogenesis of the disease. Diseases and conditions of the eye in whichanti-S1P antibodies are likely to be clinically useful include diabeticretinopathy, retinopathy of prematurity, diabetic macular edema, PVR,anterior segment diseases and age-related macular edema, both wet anddry, and after procedures such as trabeculectomy or valve implantationin glaucoma.

Anti-S1P Antibodies for the Treatment of Scleroderma

The compositions and methods of the invention will be useful in treatingdisorders and diseases characterized, at least in part, by aberrantneovascularization, angiogenesis, fibrogenesis, fibrosis, scarring,inflammation, and immune response. One such disease is scleroderma,which is also referred to as systemic sclerosis.

Scleroderma is an autoimmune disease that causes scarring or thickeningof the skin, and sometimes involves other areas of the body, includingthe lungs, heart, and/or kidneys. Scleroderma is characterized by theformation of scar tissue (fibrosis) in the skin and organs of the body,which can lead to thickening and firmness of involved areas, withconsequent reduction in function. Today, about 300,000 Americans havescleroderma, according to the Scleroderma Foundation. One-third or lessof those affected have widespread disease, while the remainingtwo-thirds primarily have skin symptoms. When the disease affects thelungs and causing scarring, breathing can become restricted because thelungs can no longer expand as they should. To measure breathingcapability, doctors use a device that assesses forced vital capacity(FVC). In people with an FVC of less than 50 percent of the expectedreading, the 1 0-year mortality rate from scleroderma-related lungdisease is about 42 percent. One reason the mortality rate is so high isthat no effective treatment is currently available.

Without wishing to be bound by any particular theory, it is believedthat inappropriate concentrations of lipids such as S1P and/or itsmetabolites, cause or contribute to the development of scleroderma. Assuch, the compositions and methods of the invention can be used to treatscleroderma, particularly by decreasing the effective in vivoconcentration of a particular target lipid, for example, S1P.

As described elsewhere in this application, existing evidence indicatesthat S1P is a pro-fibrotic growth factor that can contribute tofibroblast activation, proliferation, and the resulting increasedfibroblast activity associated with maladaptive scarring and remodeling.It is believed that S1P bioactivity with and anti-S1P agent (e.g., ananti-S1P mAb) could indirectly mitigate the pro-sclerotic effects ofPDGF and TGF-β. Moreover, treatment with such an anti-S1P agent couldbenefit scleroderma patients by mitigating the direct effects of S1P onskin and other forms of fibroblasts that contribute to diseaseprogression.

Cardiovascular and Cerebrovascular Disorders

Without wishing to be bound by any particular theory, the level ofundesirable sphingolipids such as CER, SPH, or S1P, and/or one or moreof their metabolites, may be directly responsible for cardiacdysfunction, during or after cardiac ischemia such as during reperfusioninjury and the resulting cardiac remodeling and heart failure.

Because sphingolipids such as S1P are involved in fibrogenesis and woundhealing of liver tissue (Davaille, et al., J. Biol. Chem.275:34268-34633, 2000; Ikeda, et al., Am J. Physiol. Gastrointest. LiverPhysiol 279:G304-G310, 2000), healing of wounded vasculatures (Lee, etal., Am. J. Physiol. Cell Physiol. 278:C612-C618, 2000), and otherdisease states, or events associated with such diseases, such as cancer,angiogenesis and inflammation (Pyne, et al., Biochem. J. 349:385-402,2000), the compositions and methods of the disclosure may be applied totreat not only these diseases but cardiac diseases as well.

This suggests that sphingolipids derived from cardiac or othernon-cerebral sources could contribute to stroke. Consequently,interfering with sphingolipid production and/or action may be beneficialin mitigating stroke, particularly in stroke caused by peripheralvascular disease, atherosclerosis, and cardiac disorders. Recentevidence suggests that exogenously administered S1P crosses theblood-brain barrier and promotes cerebral vasoconstriction (Tosaka, etal., Stroke 32: 2913-2919.2001).

It has been suggested that an early event in the course of cardiacischemia (i. e., lack of blood supply to the heart) is an excessproduction by the heart muscle of the naturally occurring compoundsphingosine, and that other metabolites, particularly S1P are alsoproduced either by the heart tissue itself or by components of blood asa consequence of cardiac sphingolipid production and subsequentconversion in the blood. The present invention provides methods forneutralizing S1P with specific humanized monoclonal antibodies. Thepresent invention thus provides humanized anti-sphingolipid antibodiesand related compositions and methods to reduce blood and tissue levelsof the key sphingolipid, S1P. Such antibodies are useful, for example,for binding and thus lowering the effective concentration of,undesirable sphingolipids in whole blood.

The therapeutic methods and compositions of the invention are said to be“sphingolipid-based” in order to indicate that these therapies canchange the relative, absolute or available concentration(s) of certainundesirable, toxic or cardiotoxic sphingolipids. A “toxic sphingolipid”refers to any sphingolipid that can cause or enhance the necrosis and/orapoptosis of cells or otherwise impair function of an organ or tissue(e.g., through excessive fibrosis), including, in some instances,particular cell types that are found in specific tissues or organs.“Cardiotoxic sphingolipids” are toxic sphingolipids that directly orindirectly promote heart failure through maladaptive scarring(fibrogenesis) and cause a negative inotropic state or cause or enhancethe necrosis and/or apoptosis of cells found in or associated with theheart, including but not limited to cardiomyocytes, cardiac neurons andthe like, and/or can cause loss of cardiac function due to the negativeinotropic, arrhythmic coronary vasoconstriction/spasm effects of thesphingolipids and/or their metabolites. “Undesirable sphingolipids”include toxic and cardiotoxic sphingolipids, as well as metabolites,particularly metabolic precursors, of toxic and cardiotoxicsphingolipids. Undesirable, cardiotoxic, and/or toxic sphingolipids ofparticular interest include, but are not limited to, ceramide (CER),ceraminde-1-phosphate (C1P), sphingosine-1-phosphate (S-1-P),dihydro-S1P (DHS1P), sphingosylphosphoryl choline (SPC), sphingosine(SPH; D(+)-erythro-2-amino-4-trans-octadecene-1,3-diol, or sphinganine)and various metabolites.

It is known that one of the earliest responses of cardiac myocytes tohypoxia and reoxygenation is the activation of neutral sphingomyelinaseand the accumulation of ceramide. Hernandez, et al. (2000), Circ. Res.86:198-204, 2000. SPH has been allegedly implicated as mediating anearly signaling event in apoptotic cell death in a variety of cell types(Ohta, et al., FEBS Letters 355:267-270, 1994; Ohta, et al., Cancer Res.55:691-697, 1995; Cuvlilier, et al., Nature 381:800-803, 1996). It ispostulated that the cardiotoxic effects of hypoxia may result in partfrom sphingolipid production and/or from the inappropriate production ofother metabolites (e.g., protons, calcium, and certain free radicals) orsignaling molecules (e.g., MAP kinases, caspases) that adversely affectcardiac function.

S1P is stored in platelets and is a normal constituent of human plasmaand serum (Yatomi, et al., J. Biochem. 121:969-973, 1997). S1P is acoronary vasoconstrictor and has other biological effects on caninehearts. Sugiyama, et al. (2000), Cardiovascular Res. 46:119-125. A rolefor S1P in atherosclerosis has been postulated (Siess, et al., IUBMBLife 49:161-171, 2000). This has been supported by other data, includingevidence that the protective effect of HDL is due to blocking S1Pproduction (Xia, et al., PNAS 95:14196-14201, 1988; Xia, et al., J BiolChem 274:33143-33147, 1999).

Sphingomyelin, the metabolic precursor of ceramide, has been reported tobe increased in experimental animals subjected to hypoxia (Sergeev, etal., Kosm. Biol. Aviakosm. Med. (Russian) 15:71-74, 1981). Other studieshave reported that internal membranes of muscle cells contain highamounts of SPH and sphingomyelin (Sumnicht, et al., Arch. Biochem.Biophys. 215:628-637, 1982; Sabbadini, et al., Biochem. Biophys. Res.Comm. 193752-758, 1993). Treatment of experimental animals withfumonisinB fungal toxins result in increase serum levels of SPH andDHSPH (S1P was not measured) with coincident negative inotropic effectson the heart (Smithe, et al., Toxicological Sciences 56:240-249, 2000).

Other Diseases or Conditions

Because of the involvement of bioactive lipid signaling in manyprocesses, including neovascularization, angiogenesis, aberrantfibrogenesis, fibrosis and scarring, and inflammation and immuneresponses, it is believed that inhibitors of these bioactive lipids willbe helpful in a variety of diseases and conditions associated with oneor more of these processes. Such diseases and conditions may be systemic(e.g., systemic scleroderma) or localized to one or more specific bodysystems, parts or organs (e.g., skin, lung, cardiovascular system oreye).

One way to control the amount of undesirable sphingolipids in a patientis by providing a composition that comprises one or more humanizedanti-sphingolipid antibodies to bind one or more sphingolipids, therebyacting as therapeutic “sponges” that reduce the level of freeundesirable sphingolipids. When a compound is referred to as “free”, thecompound is not in any way restricted from reaching the site or siteswhere it exerts its undesirable effects. Typically, a free compound ispresent in blood and tissue, which either is or contains the site(s) ofaction of the free compound, or from which a compound can freely migrateto its site(s) of action. A free compound may also be available to beacted upon by any enzyme that converts the compound into an undesirablecompound.

Without wishing to be bound by any particular theory, it is believedthat the level of undesirable sphingolipids such as SPH or S1P, and/orone or more of their metabolites, cause or contribute to the developmentof cardiac and myocardial diseases and disorders.

Because sphingolipids are also involved in fibrogenesis and woundhealing of liver tissue (Davaille, et al., J. Biol. Chem.275:34268-34633, 2000; Ikeda, et al., Am J. Physiol. Gastrointest. LiverPhysiol 279:G304-G310, 2000), healing of wounded vasculatures (Lee, etal., Am. J. Physiol. Cell Physiol. 278:C612-C618, 2000), and otherdisease states or disorders, or events associated with such diseases ordisorders, such as cancer, angiogenesis, various ocular diseasesassociate with excessive fibrosis and inflammation (Pyne et al.,Biochem. J. 349:385-402, 2000), the compositions and methods of thepresent disclosure may be applied to treat these diseases and disordersas well as cardiac and myocardial diseases and disorders.

One form of sphingolipid-based therapy involves manipulating themetabolic pathways of sphingolipids in order to decrease the actual,relative and/or available in vivo concentrations of undesirable, toxicsphingolipids. The invention provides compositions and methods fortreating or preventing diseases, disorders or physical trauma, in whichhumanized anti-sphingolipid antibodies are administered to a patient tobind undesirable, toxic sphingolipids, or metabolites thereof.

Such humanized anti-sphingolipid antibodies may be formulated in apharmaceutical composition that are useful for a variety of purposes,including the treatment of diseases, disorders or physical trauma.Pharmaceutical compositions comprising one or more humanizedanti-sphingolipid antibodies of the invention may be incorporated intokits and medical devices for such treatment. Medical devices may be usedto administer the pharmaceutical compositions of the invention to apatient in need thereof, and according to one embodiment of theinvention, kits are provided that include such devices. Such devices andkits may be designed for routine administration, includingself-administration, of the pharmaceutical compositions of theinvention. Such devices and kits may also be designed for emergency use,for example, in ambulances or emergency rooms, or during surgery, or inactivities where injury is possible but where full medical attention maynot be immediately forthcoming (for example, hiking and camping, orcombat situations).

Methods of Administration.

The treatment for diseases and conditions discussed herein can beachieved by administering agents and compositions of the invention byvarious routes employing different formulations and devices. Suitablepharmaceutically acceptable diluents, carriers, and excipients are wellknown in the art. One skilled in the art will appreciate that theamounts to be administered for any particular treatment protocol canreadily be determined. Suitable amounts might be expected to fall withinthe range of 10 μg/dose to 10 g/dose, preferably within 10 mg/dose to 1g/dose.

Drug substances may be administered by techniques known in the art,including but not limited to systemic, subcutaneous, intradermal,mucosal, including by inhalation, and topical administration. The mucosarefers to the epithelial tissue that lines the internal cavities of thebody. For example, the mucosa comprises the alimentary canal, includingthe mouth, esophagus, stomach, intestines, and anus; the respiratorytract, including the nasal passages, trachea, bronchi, and lungs; andthe genitalia. For the purpose of this specification, the mucosa alsoincludes the external surface of the eye, i.e., the cornea andconjunctiva. Local administration (as opposed to systemicadministration) may be advantageous because this approach can limitpotential systemic side effects, but still allow therapeutic effect.

Pharmaceutical compositions used in the present invention include, butare not limited to, solutions, emulsions, and liposome-containingformulations. These compositions may be generated from a variety ofcomponents that include, but are not limited to, preformed liquids,self-emulsifying solids and self-emulsifying semisolids.

The pharmaceutical formulations used in the present invention may beprepared according to conventional techniques well known in thepharmaceutical industry. Such techniques include the step of bringinginto association the active ingredients with the pharmaceuticalcarrier(s) or excipient(s). Preferred carriers include those that arepharmaceutically acceptable, particularly when the composition isintended for therapeutic use in humans. For non-human therapeuticapplications (e.g., in the treatment of companion animals, livestock,fish, or poultry), veterinarily acceptable carriers may be employed. Ingeneral the formulations are prepared by uniformly and intimatelybringing into association the active ingredients with liquid carriers orfinely divided solid carriers or both, and then, if necessary, shapingthe product.

The compositions of the present invention may be formulated into any ofmany possible dosage forms such as, but not limited to, tablets,capsules, liquid syrups, soft gels, suppositories, and enemas. Thecompositions of the present invention may also be formulated assuspensions in aqueous, non-aqueous or mixed media. Aqueous suspensionsmay further contain substances which increase the viscosity of thesuspension including, for example, sodium carboxymethylcellulose,sorbitol and/or dextran. The suspension may also contain stabilizers.

In one embodiment the pharmaceutical compositions may be formulated andused as foams. Pharmaceutical foams include formulations such as, butnot limited to, emulsions, microemulsions, creams, jellies, andliposomes.

While basically similar in nature these formulations vary in thecomponents and the consistency of the final product. The know-how on thepreparation of such compositions and formulations is generally known tothose skilled in the pharmaceutical and formulation arts and may beapplied to the formulation of the compositions of the present invention.

In one embodiment, an immune-derived moiety can be delivered to the eyevia, for example, topical drops or ointment, periocular injection,intracamerally into the anterior chamber or vitreous, via an implanteddepot, or systemically by injection or oral administration. The quantityof antibody used can be readily determined by one skilled in the art.

The traditional approaches to delivering therapeutics to the eye includetopical application, redistribution into the eye following systemicadministration or direct intraocular/periocular injections [Sultana, etal. (2006), Current Drug Delivery, vol 3: 207-217; Ghate and Edelhauser(2006), Expert Opinion, vol 3: 275-287; and Kaur and Kanwar (2002), DrugDevelop Industrial Pharmacy, vol 28: 473-493]. Anti-S1P or otheranti-bioactive lipid antibody therapeutics would likely be used with anyof these approaches although all have certain perceived advantages anddisadvantages. Topical drops are convenient, but wash away primarilybecause of nasolacrimal drainage often delivering less than 5% of theapplied drug into the anterior section of the eye and an even smallerfraction of that dose to the posterior segment of the globe. Besidesdrops, sprays afford another mode for topical administration. A thirdmode is ophthalmic ointments or emulsions can be used to prolong thecontact time of the formulation with the ocular surface althoughblurring of vision and matting of the eyelids can be troublesome. Suchtopical approaches are still preferable, since systemic administrationof therapeutics to treat ocular disorders exposes the whole body to thepotential toxicity of the drug.

Treatment of the posterior segment of the eye is medically importantbecause age-related macular degeneration, diabetic retinopathy,posterior uveitis, and glaucoma are the leading causes of vision loss inthe United States and other developed countries. Myles, et al. (2005),Adv Drug Deliv Rev; 57: 2063-79. The most efficient mode of drugdelivery to the posterior segment is intravitreal injection through thepars plana. However, direct injections require a skilled medicalpractitioner to effect the delivery and can cause treatment-limitinganxiety in many patients. Periocular injections, an approach thatincludes subconjunctival, retrobulbar, peribulbar and posterior subtenoninjections, are somewhat less invasive than intravitreal injections.Repeated and long-term intravitreal injections may cause complications,such as vitreous hemorrhage, retinal detachment, or endophthalmitis.

The anti-bioactive lipid antibody treatment might also be administeredusing one of the newer ocular delivery systems [Sultana, et al. (2006),Current Drug Delivery, vol 3: 207-217; and Ghate and Edelhauser (2006),Expert Opinion, vol 3: 275-287], including sustained or controlledrelease systems, such as (a) ocular inserts (soluble, erodible,non-erodible or hydrogel-based), corneal shields, eg, collagen-basedbandage and contact lenses that provide controlled delivery of drug tothe eye, (b) in situ gelling systems that provide ease of administrationas drops that get converted to gel form in the eye, thereby providingsome sustained effect of drug in the eye, (c) vesicular systems such asliposomes, niosomes/discomes, etc., that offers advantages of targeteddelivery, bio-compatibility and freedom from blurring of vision, (d)mucoadhesive systems that provide better retention in the eye, (e)prodrugs (f) penetration enhancers, (g) lyophilized carrier systems, (h)particulates, (i) submicron emulsions, (j) iontophoresis, (k)dendrimers, (l) microspheres including bioadhesive microspheres, (m)nanospheres and other nanoparticles, (n) collasomes, and (o) drugdelivery systems that combine one or more of the above stated systems toprovide an additive, or even synergistic, beneficial effect. Most ofthese approaches target the anterior segment of the eye and may bebeneficial for treating anterior segment disease. However, one or moreof these approaches still may be useful affecting bioactive lipidconcentrations in the posterior region of the eye because the relativelylow molecular weights of the lipids will likely permit considerablemovement of the lipid within the eye. In addition, the antibodyintroduced in the anterior region of the eye may be able to migratethroughout the eye especially if it is manufactured in a lower weightantibody variant such as a Fab fragment. Sustained drug delivery systemsfor the posterior segment such as those approved or under development(see references, supra) could also be employed.

As previously mentioned, the treatment of disease of the posteriorretina, choroids, and macula is medically very important. In thisregard, transscleral iontophoresis [Eljarrat-Binstock and Domb (2006),Control Release, 110: 479-89] is an important advance and may offer aneffective way to deliver antibodies to the posterior segment of the eye.

Various excipients might also be added to the formulated antibody toimprove performance of the therapy, make the therapy more convenient orto clearly ensure that the formulated antibody is used only for itsintended, approved purpose. Examples of excipients include chemicals tocontrol pH, antimicrobial agents, preservatives to prevent loss ofantibody potency, dyes to identify the formulation for ocular use only,solubilizing agents to increase the concentration of antibody in theformulation, penetration enhancers and the use of agents to adjustisotonicity and/or viscosity. Inhibitors of, e.g., proteases, could beadded to prolong the half life of the antibody. In one embodiment, theantibody is delivered to the eye by intravitreal injection in a solutioncomprising phosphate-buffered saline at a suitable pH for the eye.

The anti-S1P agent (e.g., a humanized antibody) can also be chemicallymodified to yield a pro-drug that is administered in one of theformulations or devices previously described above. The active form ofthe antibody is then released by action of an endogenous enzyme.Possible ocular enzymes to be considered in this application are thevarious cytochrome p450s, aldehyde reductases, ketone reductases,esterases or N-acetyl-β-glucosamidases. Other chemical modifications tothe antibody could increase its molecular weight, and as a result,increase the residence time of the antibody in the eye. An example ofsuch a chemical modification is pegylation [Harris and Chess (2003), NatRev Drug Discov; 2: 214-21], a process that can be general or specificfor a functional group such as disulfide [Shaunak, et al. (2006), NatChem Biol ; 2:312-3] or a thiol [Doherty, et al. (2005), Bioconjug Chem;16: 1291-8].

The examples herein below describe the production of humanized andvariant anti-sphingolipid antibodies with desirable properties from atherapeutic perspective, including strong binding affinity forsphingolipids. In particular, the invention is drawn to S1P and itsvariants which may include S1P itself defined as sphingosine-1-phosphate[sphingene-1-phosphate; D-erythro-sphingosine-1-phosphate;sphing-4-enine-1-phosphate;(E,2S,3R)-2-amino-3-hydroxy-octadec-4-enoxy]phosphonic acid (AS26993-30-6), DHS1P is defined as dihydrosphingosine-1-phosphate[sphinganine-1-phosphate;[(2S,3R)-2-amino-3-hydroxy-octadecoxy]phosphonic acid;D-Erythro-dihydro-D-sphingosine-1-phospate (CAS 19794-97-9]; SPC issphingosylphosphoryl choline, lysosphingomyelin,sphingosylphosphocholine, sphingosine phosphorylcholine, ethanaminium;2-((((2-amino-3-hydroxy-4-octadecenyl)oxy)hydroxyphosphinyl)oxy)-N,N,N-trimethyl-,chloride, (R-(R*,S*-(E))), 2-[[(E,2R,3S)-2-amino-3-hydroxy-octadec-4-enoxy]-hydroxy-phosphoryl]oxyethy1-trimethyl-azanium chloride (CAS 10216-23-6).

Antibody Generation and Characterization

Antibody affinities may be determined as described in the examplesherein below. Preferred humanized or variant antibodies are those whichbind a sphingolipid with a K_(d) value of no more than about 1×10⁻⁷ M,preferably no more than about 1×10⁻⁸ M, and most preferably no more thanabout 5×10⁻⁹ M.

Aside from antibodies with strong binding affinity for sphingolipids, itis also desirable to select humanized or variant antibodies that haveother beneficial properties from a therapeutic perspective. For example,the antibody may be one that reduce angiogenesis and alter tumorprogression. Preferably, the antibody has an effective concentration 50(EC50) value of no more than about 10 ug/ml, preferably no more thanabout 1 ug/ml, and most preferably no more than about 0.1 ug/ml, asmeasured in a direct binding ELISA assay. Preferably, the antibody hasan effective concentration value of no more than about 10 ug/ml,preferably no more than about 1 ug/ml, and most preferably no more thanabout 0.1 ug/ml, as measured in cell assays in presence of 1 uM of S1P,for example, at these concentrations the antibody is able to inhibitsphingolipid-induced IL-8 release in vitro by at least 10%. Preferably,the antibody has an effective concentration value of no more than about10 ug/ml, preferably no more than about 1 ug/ml, and most preferably nomore than about 0.1 ug/ml, as measured in the CNV animal model afterlaser burn, for example, at these concentrations the antibody is able toinhibit sphingolipid-induced neovascularization in vivo by at least 50%.

Assays for determining the activity of the anti-sphingolipid antibodiesof the invention include ELISA assays as shown in the exampleshereinbelow.

Preferably the humanized or variant antibody fails to elicit animmunogenic response upon administration of a therapeutically effectiveamount of the antibody to a human patient. If an immunogenic response iselicited, preferably the response will be such that the antibody stillprovides a therapeutic benefit to the patient treated therewith.

According to one embodiment of the invention, humanizedanti-sphingolipid antibodies bind the “epitope” as herein defined. Toscreen for antibodies that bind to the epitope on a sphingolipid boundby an antibody of interest (e.g., those that block binding of theantibody to sphingolipid), a routine cross-blocking assay such as thatdescribed in Antibodies, A Laboratory Manual, Cold Spring HarborLaboratory, Ed Harlow and David Lane (1988), can be performed.Alternatively, epitope mapping, e.g., as described in Champe, et al. [J.Biol. Chem. 270:1388-1394 (1995)], can be performed to determine whetherthe antibody binds an epitope of interest.

The antibodies of the invention have a heavy chain variable domaincomprising an amino acid sequence represented by the formula:FR1-CDRH1-FR2-CDRH2-FR3-CDRH3-FR4, wherein “FR1-4” represents the fourframework regions and “CDRH1-3” represents the three hypervariableregions of an anti-sphingolipid antibody variable heavy domain. FR1-4may be derived from a “consensus sequence” (for example the most commonamino acids of a class, subclass or subgroup of heavy or light chains ofhuman immunoglobulins) as in the examples below or may be derived froman individual human antibody framework region or from a combination ofdifferent framework region sequences. Many human antibody frameworkregion sequences are compiled in Kabat, et al., supra, for example. Inone embodiment, the variable heavy FR is provided by a consensussequence of a human immunoglobulin subgroup as compiled by Kabat, etal., above. Preferably, the human immunoglobulin subgroup is human heavychain subgroup III (e.g., as in SEQ ID NO:16).

The human variable heavy FR sequence preferably has one or moresubstitutions therein, e.g., wherein the human FR residue is replaced bya corresponding nonhuman residue (by “corresponding nonhuman residue” ismeant the nonhuman residue with the same Kabat positional numbering asthe human residue of interest when the human and nonhuman sequences arealigned), but replacement with the nonhuman residue is not necessary.For example, a replacement FR residue other than the correspondingnonhuman residue can be selected by phage display. Exemplary variableheavy FR residues which may be substituted include any one or more of FRresidue numbers: 37H, 49H, 67H, 69H, 71H, 73H, 75H, 76H, 78H, and 94H(Kabat residue numbering employed here). Preferably at least two, or atleast three, or at least four of these residues are substituted. Aparticularly preferred combination of FR substitutions is: 49H, 69H,71H, 73H, 76H, 78H, and 94H. With respect to the heavy chainhypervariable regions, these preferably have amino acid sequences listedin Table 2, below.

The antibodies of the preferred embodiment herein have a light chainvariable domain comprising an amino acid sequence represented by theformula: FR1-CDRL1-FR2-CDRL2-FR3-CDRL3-FR4, wherein “FR1-4” representsthe four framework regions and “CDRL1-3” represents the threehypervariable regions of an anti-sphingolipid antibody variable heavydomain. FR1-4 may be derived from a “consensus sequence” (for example,the most common amino acids of a class, subclass or subgroup of heavy orlight chains of human immunoglobulins) as in the examples below or maybe derived from an individual human antibody framework region or from acombination of different framework region sequences. In one preferredembodiment, the variable light FR is provided by a consensus sequence ofa human immunoglobulin subgroup as compiled by Kabat, et al., above.Preferably, the human immunoglobulin subgroup is human kappa lightchains subgroup I (e.g., as in SEQ ID NO: 17).

The human variable light FR sequence preferably has substitutionstherein, e.g., wherein a human FR residue is replaced by a correspondingmouse residue, but replacement with the nonhuman residue is notnecessary. For example, a replacement residue other than thecorresponding nonhuman residue may be selected by phage display.Exemplary variable light FR residues that may be substituted include anyone or more of FR residue numbers, including, but not limited to, F4,Y36, Y49, G64, S67.

With respect to the CDRs, these preferably have amino acid sequenceslisted in Table 2, below.

Methods for generating humanized anti-sphingolipid antibodies ofinterest herein are elaborated in more detail below.

A. Antibody Preparation

Methods for humanizing nonhuman anti-sphingolipid antibodies andgenerating variants of anti-sphingolipid antibodies are described in theExamples below. In order to humanize an anti-sphingolipid antibody, thenonhuman antibody starting material is prepared. Where a variant is tobe generated, the parent antibody is prepared. Exemplary techniques forgenerating such nonhuman antibody starting material and parentantibodies will be described in the following sections.

(i) Antigen Preparation.

The sphingolipid antigen to be used for production of antibodies may be,e.g., intact sphingolipid or a portion of a sphingolipid (e.g., asphingolipid fragment comprising an “epitope”). Other forms of antigensuseful for generating antibodies will be apparent to those skilled inthe art. The sphingolipid antigen used to generate the antibody, isdescribed in the examples below. In one embodiment, the antigen is aderivatized form of the sphingolipid, and may be associated with acarrier protein.

(ii) Polyclonal Antibodies.

Polyclonal antibodies are preferably raised in animals by multiplesubcutaneous (sc) or intraperitoneal (ip) injections of the relevantantigen and an adjuvant. It may be useful to conjugate the relevantantigen to a protein that is immunogenic in the species to be immunized,e.g., keyhole limpet hemocyanin, serum albumin, bovine thyroglobulin, orsoybean trypsin inhibitor using a bifunctional or derivatizing agent,for example, maleimidobenzoyl sulfosuccinimide ester (conjugationthrough cysteine residues), N-hydroxysuccinimide (through lysineresidues), glutaraldehyde, succinic anhydride, SOCl₂, or R¹N═C═NR, whereR and R¹ are different alkyl groups.

Animals are immunized against the antigen, immunogenic conjugates, orderivatives by combining, e.g., 100 ug or 5 ug of the protein orconjugate (for rabbits or mice, respectively) with three volumes ofFreund's complete adjuvant and injecting the solution intradermally atmultiple sites. One month later the animals are boosted with 0.1 to 0.2times the original amount of peptide or conjugate in Freun's completeadjuvant by subcutaneous injection at multiple sites. Seven to 14 dayslater the animals are bled and the serum is assayed for antibody titer.Animals are boosted until the titer plateaus. Preferably, the animal isboosted with the conjugate of the same antigen, but conjugated to adifferent protein and/or through a different cross-linking reagent.Conjugates also can be made in recombinant cell culture as proteinfusions. Also, aggregating agents such as alum may be suitably used toenhance the immune response.

(iii) Monoclonal Antibodies.

Monoclonal antibodies may be made using the hybridoma method firstdescribed by Kohler, et al., Nature, 256:495 (1975), or by othersuitable methods, including by recombinant DNA methods (see, e.g., U.S.Pat. No. 4,816,567). In the hybridoma method, a mouse or otherappropriate host animal, such as a hamster or macaque monkey, isimmunized as hereinabove described to elicit lymphocytes that produce orare capable of producing antibodies that will specifically bind to theprotein used for immunization. Alternatively, lymphocytes may beimmunized in vitro. Lymphocytes then are fused with myeloma cells usinga suitable fusing agent, such as polyethylene glycol, to form ahybridoma cell (Goding, Monoclonal Antibodies: Principles and Practice,pp.59-103 (Academic Press, 1986)).

The hybridoma cells thus prepared are seeded and grown in a suitableculture medium that preferably contains one or more substances thatinhibit the growth or survival of the unfused, parental myeloma cells.For example, if the parental myeloma cells lack the enzyme hypoxanthineguanine phosphoribosyl transferase (HGPRT or HPRT), the culture mediumfor the hybridomas typically will include hypoxanthine, aminopterin, andthymidine (HAT medium), which substances prevent the growth ofHGPRT-deficient cells.

Preferred myeloma cells are those that fuse efficiently, support stablehigh-level production of antibody by the selected antibody-producingcells, and are sensitive to a medium such as HAT medium. Among these,preferred myeloma cell lines are murine myeloma lines, such as thosederived from MOP-21 and M.C.-11 mouse tumors available from the SalkInstitute Cell Distribution Center, San Diego, Calif. USA, and SP-2 orX63-Ag8-653 cells available from the American Type Culture Collection,Rockville, Md. USA. Human myeloma and mouse-human heteromyeloma celllines also have been described for the production of human monoclonalantibodies (Kozbor, J. Immunol., 133:3001 (1984); Brodeur, et al.,Monoclonal Antibody Production Techniques and Applications, pp. 51-63(Marcel Dekker, Inc., New York, 1987)).

Culture medium in which hybridoma cells are growing is assayed forproduction of monoclonal antibodies directed against the antigen.Preferably, the binding specificity of monoclonal antibodies produced byhybridoma cells is determined by immunoprecipitation or by an in vitrobinding assay, such as radioimmunoassay (RIA) or enzyme-linkedimmunoabsorbant assay (ELISA).

The binding affinity of a monoclonal antibody can, for example, bedetermined by the Scatchard analysis of Munson, et al., Anal. Biochem.,107:220 (1980).

After hybridoma cells are identified that produce antibodies of thedesired specificity, affinity, and/or activity, the clones may besubcloned by limiting dilution procedures and grown by standard methods(Goding, Monoclonal Antibodies: Principles and Practice, pp.59-103(Academic Press, 1986)). Suitable culture media for this purposeinclude, for example, D-MEM or RPMI-1640 medium. In addition, thehybridoma cells may be grown in vivo as ascites tumors in an animal.

The monoclonal antibodies secreted by the subclones are suitablyseparated from the culture medium, ascites fluid, or serum byconventional immunoglobulin purification procedures such as, forexample, protein A-Sepharose, hydroxylapatite chromatography, gelelectrophoresis, dialysis, or affinity chromatography.

DNA encoding the monoclonal antibodies is readily isolated and sequencedusing conventional procedures (e.g., by using oligonucleotide probesthat are capable of binding specifically to genes encoding the heavy andlight chains of the monoclonal antibodies). The hybridoma cells serve asa preferred source of such DNA. Once isolated, the DNA may be placedinto expression vectors, which are then transfected into host cells suchas E. coli cells, simian COS cells, Chinese hamster ovary (CHO) cells,or myeloma cells that do not otherwise produce immunoglobulin protein,to obtain the synthesis of monoclonal antibodies in the recombinant hostcells. Recombinant production of antibodies will be described in moredetail below.

(iv) Humanization and Amino Acid Sequence Variants.

Example 12, below, describes procedures for humanization of ananti-sphingolipid antibody. General methods for humanization aredescribed in, for example, U.S. Pat. No. 5,861,155, US19960652558, U.S.Pat. No. 6,479,284, US20000660169, U.S. Pat. No. 6,407,213, US19930146206, U.S. Pat. No. 6,639,055, US20000705686, U.S. Pat. No.6,500,931, US19950435516, U.S. Pat. No. 5,530,101, U.S. Pat. No.5,585,089, US19950477728, U.S. Pat. No. 5,693,761, US 19950474040, U.S.Pat. No. 5,693,762, US 19950487200, U.S. Pat. No. 6,180,370, US19950484537, US2003229208, US20030389155, U.S. Pat. No. 5,714,350,US19950372262, U.S. Pat. No. 6,350,861, US19970862871, U.S. Pat. No.5,777,085, US19950458516, U.S. Pat. No. 5,834,597, US19960656586, U.S.Pat. No. 5,882,644, US19960621751, U.S. Pat. No. 5,932,448,US19910801798, U.S. Pat. No. 6,013,256, US19970934841, U.S. Pat. No.6,129,914, US19950397411, U.S. Pat. No. 6,210,671, U.S. Pat. No.6,329,511, US19990450520, US2003166871, US20020078757, U.S. Pat. No.5,225,539, US19910782717, U.S. Pat. No. 6,548,640, US19950452462, U.S.Pat. No. 5,624,821, and US19950479752. In certain embodiments, it may bedesirable to generate amino acid sequence variants of these humanizedantibodies, particularly where these improve the binding affinity orother biological properties of the humanized antibody. Example 12describes methodologies for generating amino acid sequence variants ofan anti-sphingolipid antibody with enhanced affinity relative to theparent antibody.

Amino acid sequence variants of the anti-sphingolipid antibody areprepared by introducing appropriate nucleotide changes into theanti-sphingolipid antibody DNA, or by peptide synthesis. Such variantsinclude, for example, deletions from, and/or insertions into and/orsubstitutions of, residues within the amino acid sequences of theanti-sphingolipid antibodies of the examples herein. Any combination ofdeletion, insertion, and substitution is made to arrive at the finalconstruct, provided that the final construct possesses the desiredcharacteristics. The amino acid changes also may alterpost-translational processes of the humanized or variantanti-sphingolipid antibody, such as changing the number or position ofglycosylation sites.

A useful method for identification of certain residues or regions of theanti-sphingolipid antibody that are preferred locations for mutagenesisis called “alanine scanning mutagenesis,” as described by Cunningham andWells Science, 244:1081-1085 (1989). Here, a residue or group of targetresidues are identified (e.g., charged residues such as arg, asp, his,lys, and glu) and replaced by a neutral or negatively charged amino acid(most preferably alanine or polyalanine) to affect the interaction ofthe amino acids with sphingolipid antigen. Those amino acid locationsdemonstrating functional sensitivity to the substitutions then arerefined by introducing further or other variants at, or for, the sitesof substitution. Thus, while the site for introducing an amino acidsequence variation is predetermined, the nature of the mutation per seneed not be predetermined. For example, to analyze the performance of amutation at a given site, ala scanning or random mutagenesis isconducted at the target codon or region and the expressedanti-sphingolipid antibody variants are screened for the desiredactivity. Amino acid sequence insertions include amino- and/orcarboxyl-terminal fusions ranging in length from one residue topolypeptides containing a hundred or more residues, as well asintrasequence insertions of single or multiple amino acid residues.Examples of terminal insertions include an anti-sphingolipid antibodywith an N-terminal methionyl residue or the antibody fused to an epitopetag. Other insertional variants of the anti-sphingolipid antibodymolecule include the fusion to the N- or C-terminus of theanti-sphingolipid antibody of an enzyme or a polypeptide which increasesthe serum half-life of the antibody.

Another type of variant is an amino acid substitution variant. Thesevariants have at least one amino acid residue in the anti-sphingo lipidantibody molecule removed and a different residue inserted in its place.The sites of greatest interest for substitutional mutagenesis includethe hypervariable regions, but FR alterations are also contemplated.Conservative substitutions are preferred sub stitutions. If suchsubstitutions result in a change in biological activity, then moresubstantial changes, denominated “exemplary” substitutions listed below,or as further described below in reference to amino acid classes, may beintroduced and the products screened.

TABLE 1 Exemplary Amino Acid Residue Substitutions Amino acid residue(symbol) Exemplary substitutions Ala (A) val; leu; ile val Arg (R) lys;gln; asn lys Asn (N) gln; his; asp, lys; gln arg Asp (D) glu; asn gluCys (C) ser; ala ser Gln (Q) asn; glu asn Glu (E) asp; gln asp Gly (G)ala ala His (H) asn; gln; lys; arg arg Ile (I) leu; val; met; ala; leuphe; norleucine Leu (L) norleucine; ile; val; ile met; ala; phe Lys (K)arg; gln; asn arg Met (M) leu; phe; ile leu Phe (F) leu; val; ile; ala;tyr tyr Pro (P) ala ala Ser (S) thr thr Thr (T) ser ser Trp (W) tyr; phetyr Tyr (Y) trp; phe; thr; ser phe Val (V) ile; leu; met; phe; leu ala;norleucine

Substantial modifications in the biological properties of the antibodyare accomplished by selecting substitutions that differ significantly intheir effect on maintaining (a) the structure of the polypeptidebackbone in the area of the substitution, for example, as a sheet orhelical conformation, (b) the charge or hydrophobicity of the moleculeat the target site, or (c) the bulk of the side chain. Naturallyoccurring residues are divided into groups based on common side-chainproperties:

(1) hydrophobic: norleucine, met, ala, val, leu, ile;

(2) neutral hydrophilic: cys, ser, thr;

(3) acidic: asp, glu;

(4) basic: asn, gln, his, lys, arg;

(5) residues that influence chain orientation: gly, pro; and

(6) aromatic: trp, tyr, phe.

Non-conservative substitutions will entail exchanging a member of one ofthese classes for another class.

Any cysteine residue not involved in maintaining the proper conformationof the humanized or variant anti-sphingolipid antibody also may besubstituted, to improve the oxidative stability of the molecule andprevent aberrant crosslinking. Conversely, cysteine bond(s) may be addedto the antibody to improve its stability (particularly where theantibody is an antibody fragment such as an Fv fragment).

One type of substitutional variant involves substituting one or morehypervariable region residues of a parent antibody (e.g., a humanized orhuman antibody). Generally, the resulting variant(s) selected forfurther development will have improved biological properties relative tothe parent antibody from which they are generated. A convenient way forgenerating such substitutional variants is affinity maturation usingphage display. Briefly, several hypervariable region sites (e.g., 6-7sites) are mutated to generate all possible amino substitutions at eachsite. The antibody variants thus generated are displayed in a monovalentfashion from filamentous phage particles as fusions to the gene IIIIproduct of M13 packaged within each particle. The phage-displayedvariants are then screened for their biological activity (e.g., bindingaffinity) as herein disclosed. In order to identify candidatehypervariable region sites for modification, alanine scanningmutagenesis can be performed to identify hypervariable region residuescontributing significantly to antigen binding. Alternatively, or inaddition, it may be beneficial to analyze a crystal structure of theantigen-antibody complex to identify contact points between the antibodyand sphingolipid. Such contact residues and neighboring residues arecandidates for substitution according to the techniques elaboratedherein. Once such variants are generated, the panel of variants issubjected to screening as described herein and antibodies with superiorproperties in one or more relevant assays may be selected for furtherdevelopment.

Another type of amino acid variant of the antibody alters the originalglycosylation pattern of the antibody. By altering is meant deleting oneor more carbohydrate moieties found in the antibody, and/or adding oneor more glycosylation sites that are not present in the antibody.

Glycosylation of antibodies is typically either N-linked and/or orO-linked. N-linked refers to the attachment of the carbohydrate moietyto the side chain of an asparagine residue. The tripeptide sequencesasparagine-X-serine and asparagine-X-threonine, where X is any aminoacid except proline, are the most common recognition sequences forenzymatic attachment of the carbohydrate moiety to the asparagine sidechain. Thus, the presence of either of these tripeptide sequences in apolypeptide creates a potential glycosylation site. O-linkedglycosylation refers to the attachment of one of the sugarsN-aceylgalactosamine, galactose, or xylose to a hydroxyamino acid, mostcommonly serine or threonine, although 5-hydroxyproline or5-hydroxylysine may also be used.

Addition of glycosylation sites to the antibody is convenientlyaccomplished by altering the amino acid sequence such that it containsone or more of the above-described tripeptide sequences (for N-linkedglycosylation sites). The alteration may also be made by the additionof, or substitution by, one or more serine or threonine residues to thesequence of the original antibody (for O-linked glycosylation sites).

Nucleic acid molecules encoding amino acid sequence variants of theanti-sphingolipid antibody are prepared by a variety of methods known inthe art. These methods include, but are not limited to, isolation from anatural source (in the case of naturally occurring amino acid sequencevariants) or preparation by oligonucleotide-mediated (or site-directed)mutagenesis, PCR mutagenesis, and cassette mutagenesis of an earlierprepared variant or a non-variant version of the anti-sphingolipidantibody.

(v) Human Antibodies.

As an alternative to humanization, human antibodies can be generated.For example, it is now possible to produce transgenic animals (e.g.,mice) that are capable, upon immunization, of producing a fullrepertoire of human antibodies in the absence of endogenousimmunoglobulin production. For example, it has been described that thehomozygous deletion of the antibody heavy-chain joining region (JH) genein chimeric and germ-line mutant mice results in complete inhibition ofendogenous antibody production. Transfer of the human germ-lineimmunoglobulin gene array in such germ-line mutant mice will result inthe production of human antibodies upon antigen challenge. See, e.g.,Jakobovits, et al., Proc. Natl. Acad. Sci. USA, 90:2551 (1993);Jakobovits, et al., Nature, 362:255-258(1993); Bruggermann, et al., Yearin Immuno., 7:33 (1993); and U.S. Pat. Nos. 5,591,669, 5,589,369 and5,545,807. Human antibodies can also be derived from phage-displaylibraries (Hoogenboom, et al., J. Mol. Biol., 227:381 (1991); Marks, etal., J. Mol. Biol., 222:581-597 (1991); and U.S. Pat. Nos. 5,565,332 and5,573,905). As discussed above, human antibodies may also be generatedby in vitro activated B cells (see, e.g., U.S. Pat. Nos. 5,567,610 and5,229,275) or by other suitable methods.

(vi) Antibody Fragments.

In certain embodiments, the humanized or variant anti-sphingolipidantibody is an antibody fragment. Various techniques have been developedfor the production of antibody fragments. Traditionally, these fragmentswere derived via proteolytic digestion of intact antibodies (see, e.g.,Morimoto, et al., Journal of Biochemical and Biophysical Methods24:107-117(1992); and Brennan, et al., Science 229:81 (1985)). However,these fragments can now be produced directly by recombinant host cells.For example, Fab′-SH fragments can be directly recovered from E. coliand chemically coupled to form F(ab′)₂ fragments (Carter, et al.,Bio/Technology 10: 163-167 (1992)). In another embodiment, the F(ab′)₂is formed using the leucine zipper GCN4 to promote assembly of theF(ab′)₂ molecule. According to another approach, Fv, Fab or F(ab′)₂fragments can be isolated directly from recombinant host cell culture.Other techniques for the production of antibody fragments will beapparent to the skilled practitioner.

(vii) Multispecific Antibodies.

In some embodiments, it may be desirable to generate multispecific(e.g., bispecific) humanized or variant anti-sphingolipid antibodieshaving binding specificities for at least two different epitopes.Exemplary bispecific antibodies may bind to two different epitopes ofthe sphingolipid. Alternatively, an anti-sphingolipid arm may becombined with an arm which binds to a different molecule. Bispecificantibodies can be prepared as full length antibodies or antibodyfragments (e.g., F(ab′)₂ bispecific antibodies).

According to another approach for making bispecific antibodies, theinterface between a pair of antibody molecules can be engineered tomaximize the percentage of heterodimers that are recovered fromrecombinant cell culture. The preferred interface comprises at least apart of the C_(H)3 domain of an antibody constant domain. In thismethod, one or more small amino acid side chains from the interface ofthe first antibody molecule are replaced with larger side chains (e.g.,tyrosine or tryptophan). Compensatory “cavities” of identical or similarsize to the large side chain(s) are created on the interface of thesecond antibody molecule by replacing large amino acid side chains withsmaller ones (e.g., alanine or threonine). This provides a mechanism forincreasing the yield of the heterodimer over other unwanted end-productssuch as homodimers. See, e.g., U.S. Pat. No. 5,731,168.

Bispecific antibodies include cross-linked or “heteroconjugate”antibodies. For example, one of the antibodies in the heteroconjugatecan be coupled to avidin, the other to biotin. Heteroconjugateantibodies may be made using any convenient cross-linking methods.Suitable cross-linking agents are well known in the art, and aredisclosed in, for example, U.S. Pat. No. 4,676,980, along with a numberof cross-linking techniques.

Techniques for generating bispecific antibodies from antibody fragmentshave also been described in the literature. For example, bispecificantibodies can be prepared using chemical linkage. Brennan, et al.,Science 229:81 (1985) describe a procedure wherein intact antibodies areproteolytically cleaved to generate F(ab′)₂ fragments. These fragmentsare reduced in the presence of the dithiol complexing agent sodiumarsenite to stabilize vicinal dithiols and prevent intermoleculardisulfide formation. The Fab′ fragments generated are then converted tothionitrobenzoate (TNB) derivatives. One of the Fab′-TNB derivatives isthen reconverted to the Fab′-thiol by reduction with mercaptoethylamineand is mixed with an equimolar amount of the other Fab′-TNB derivativeto form the bispecific antibody. The bispecific antibodies produced canbe used as agents for the selective immobilization of enzymes. In yet afurther embodiment, Fab′-SH fragments directly recovered from E. colican be chemically coupled in vitro to form bispecific antibodies.Shalaby, et al., J. Exp. Med. 175:217-225 (1992).

Various techniques for making and isolating bispecific antibodyfragments directly from recombinant cell culture have also beendescribed. For example, bispecific antibodies have been produced usingleucine zippers. Kostelny, et al., J. Immunol. 148(5):1547-1553 (1992).The leucine zipper peptides from the Fos and Jun proteins were linked tothe Fab′ portions of two different antibodies by gene fusion. Theantibody homodimers were reduced at the hinge region to form monomersand then re-oxidized to form the antibody heterodimers. This method canalso be utilized for the production of antibody homodimers. The“diabody” technology described by Hollinger, et al., Proc. Natl. Acad.Sci. USA 90:6444-6448 (1993) has provided an alternative mechanism formaking bispecific antibody fragments. The fragments comprise aheavy-chain variable domain (VH) connected to a light-chain variabledomain (VL) by a linker that is too short to allow pairing between thetwo domains on the same chain. Accordingly, the VH and VL domains of onefragment are forced to pair with the complementary VL and VH domains ofanother fragment, thereby forming two antigen-binding sites. Anotherstrategy for making bispecific antibody fragments by the use ofsingle-chain Fv (sFv) dimers has also been reported. See, e.g., Gruber,et al., J. Immunol. 152:5368 (1994). Alternatively, the bispecificantibody may be a “linear antibody” produced as described in, frorexample, Zapata, et al. Protein Eng. 8(10):1057-1062 (1995).

Antibodies with more than two valencies are also contemplated. Forexample, trispecific antibodies can be prepared. Tutt et al., J.Immunol. 147:60 (1991).

An antibody (or polymer or polypeptide) of the invention comprising oneor more binding sites per arm or fragment thereof will be referred toherein as “multivalent” antibody. For example a “bivalent” antibody ofthe invention comprises two binding sites per Fab or fragment thereofwhereas a “trivalent” polypeptide of the invention comprises threebinding sites per Fab or fragment thereof. In a multivalent polymer ofthe invention, the two or more binding sites per Fab may be binding tothe same or different antigens. For example, the two or more bindingsites in a multivalent polypeptide of the invention may be directedagainst the same antigen, for example against the same parts or epitopesof said antigen or against two or more same or different parts orepitopes of said antigen; and/or may be directed against differentantigens; or a combination thereof. Thus, a bivalent polypeptide of theinvention for example may comprise two identical binding sites, maycomprise a first binding sites directed against a first part or epitopeof an antigen and a second binding site directed against the same partor epitope of said antigen or against another part or epitope of saidantigen; or may comprise a first binding sites directed against a firstpart or epitope of an antigen and a second binding site directed againstthe a different antigen. However, as will be clear from the descriptionhereinabove, the invention is not limited thereto, in the sense that amultivalent polypeptide of the invention may comprise any number ofbinding sites directed against the same or different antigens.

An antibody (or polymer or polypeptide) of the invention that containsat least two binding sites per Fab or fragment thereof, in which atleast one binding site is directed against a first antigen and a secondbinding site directed against a second antigen different from the firstantigen, will also be referred to as “multispecific”. Thus, a“bispecific” polymer comprises at least one site directed against afirst antigen and at least one a second site directed against a secondantigen, whereas a “trispecific” is a polymer that comprises at leastone binding site directed against a first antigen, at least one furtherbinding site directed against a second antigen, and at least one furtherbinding site directed against a third antigen, etc. Accordingly, intheir simplest form, a bispecific polypeptide of the invention is abivalent polypeptide (per Fab) of the invention. However, as will beclear from the description hereinabove, the invention is not limitedthereto, in the sense that a multispecific polypeptide of the inventionmay comprise any number of binding sites directed against two or moredifferent antigens.

(viii) Other Modifications.

Other modifications of the humanized or variant anti-sphingolipidantibody are contemplated. For example, the invention also pertains toimmunoconjugates comprising the antibody described herein conjugated toa cytotoxic agent such as a toxin (e.g., an enzymatically active toxinof bacterial, fungal, plant or animal origin, or fragments thereof), ora radioactive isotope (for example, a radioconjugate). Conjugates aremade using a variety of bifunctional protein coupling agents such asN-succinimidyl-3-(2-pyridyldithiol) propionate (SPDP), iminothiolane(IT), bifunctional derivatives of imidoesters (such as dimethyladipimidate HCL), active esters (such as disuccinimidyl suberate),aldehydes (such as glutaraldehyde), bis-azido compounds (such as bis(p-azidobenzoyl)hexanediamine), bis-diazonium derivatives (such asbis-(p-diazoniumbenzoyl)-ethylenediamine), diisocyanates (such astolyene 2,6-diisocyanate), and bis-active fluorine compounds (such as1,5-difluoro-2,4-dinitrobenzene).

The anti-sphingolipid antibodies disclosed herein may also be formulatedas immunoliposomes. Liposomes containing the antibody are prepared bymethods known in the art, such as described in Epstein et al., Proc.Natl. Acad. Sci. USA 82:3688 (1985); Hwang, et al., Proc. Natl Acad.Sci. USA 77:4030 (1980); and U.S. Pat. Nos. 4,485,045 and 4,544,545.Liposomes with enhanced circulation time are disclosed in U.S. Pat. No.5,013,556. For example, liposomes can be generated by the reverse phaseevaporation method with a lipid composition comprising phosphatidylcholine, cholesterol and PEG-derivatized phosphatidylethanolamine(PEG-PE). Liposomes are extruded through filters of defined pore size toyield liposomes with the desired diameter. Fab′ fragments of theantibody of the present invention can be conjugated to the liposomes asdescribed in Martin, et al., J. Biol. Chem. 257:286-288 (1982) via adisulfide interchange reaction. Another active ingredient is optionallycontained within the liposome.

Enzymes or other polypeptides can be covalently bound to theanti-sphingolipid antibodies by techniques well known in the art such asthe use of the heterobifunctional crosslinking reagents discussed above.Alternatively, fusion proteins comprising at least the antigen bindingregion of an antibody of the invention linked to at least a functionallyactive portion of an enzyme of the invention can be constructed usingrecombinant DNA techniques well known in the art (see, e.g., Neuberger,et al., Nature 312:604-608 (1984)).

In certain embodiments of the invention, it may be desirable to use anantibody fragment, rather than an intact antibody, to increasepenetration of target tissues and cells, for example. In this case, itmay be desirable to modify the antibody fragment in order to increaseits serum half life. This may be achieved, for example, by incorporationof a salvage receptor binding epitope into the antibody fragment (e.g.,by mutation of the appropriate region in the antibody fragment or byincorporating the epitope into a peptide tag that is then fused to theantibody fragment at either end or in the middle, e.g., by DNA orpeptide synthesis). See, e.g., U.S. Pat. No. 6,096,871.

Covalent modifications of the humanized or variant anti-sphingolipidantibody are also included within the scope of this invention. They maybe made by chemical synthesis or by enzymatic or chemical cleavage ofthe antibody, if applicable. Other types of covalent modifications ofthe antibody are introduced into the molecule by reacting targeted aminoacid residues of the antibody with an organic derivatizing agent that iscapable of reacting with selected side chains or the N- or C-terminalresidues. Exemplary covalent modifications of polypeptides are describedin U.S. Pat. No. 5,534,615, specifically incorporated herein byreference. A preferred type of covalent modification of the antibodycomprises linking the antibody to one of a variety of nonproteinaceouspolymers, e.g., polyethylene glycol, polypropylene glycol, orpolyoxyalkylenes, in the manner set forth in U.S. Pat. Nos. 4,640,835;4,496,689; 4,301,144; 4,670,417; 4,791,192 or 4,179,337.

B. Vectors, Host Cells and Recombinant Methods

The invention also provides isolated nucleic acid encoding the humanizedor variant anti-sphingolipid antibody, vectors and host cells comprisingthe nucleic acid, and recombinant techniques for the production of theantibody.

For recombinant production of the antibody, the nucleic acid encoding itmay be isolated and inserted into a replicable vector for furthercloning (amplification of the DNA) or for expression. In anotherembodiment, the antibody may be produced by homologous recombination,e.g., as described in U.S. Pat. No. 5,204,244. DNA encoding themonoclonal antibody is readily isolated and sequenced using conventionalprocedures (e.g., by using oligonucleotide probes that are capable ofbinding specifically to genes encoding the heavy and light chains of theantibody). Many vectors are available. The vector components generallyinclude, but are not limited to, one or more of the following: a signalsequence, an origin of replication, one or more marker genes, anenhancer element, a promoter, and a transcription termination sequence,as described, for example, in U.S. Pat. No. 5,534,615.

Suitable host cells for cloning or expressing the DNA in the vectorsherein are the prokaryote, yeast, or higher eukaryote cells describedabove. Suitable prokaryotes for this purpose include eubacteria, such asGram-negative or Gram-positive organisms, for example,Enterobacteriaceae such as Escherichia, e.g., E. coli, Enterobacter,Erwinia, Klebsiella, Proteus, Salmonella, e.g., Salmonella typhimurium,Serratia, e.g., Serratia marcescans, and Shigella, as well as Bacillisuch as B. subtilis and B. licheniformis (e.g., B. licheniformis 41P),Pseudomonas such as P. aeruginosa, and Streptomyces. One preferred E.coli cloning host is E. coli 294 (ATCC 31,446), although other strainssuch as E. coli B, E. coli X1776 (ATCC 31,537), and E. coli W3110 (ATCC27,325) are suitable. These examples are illustrative rather thanlimiting.

In addition to prokaryotes, eukaryotic microbes such as filamentousfungi or yeast are suitable cloning or expression hosts foranti-sphingolipid antibody-encoding vectors. Saccharomyces cerevisiae,or common baker's yeast, is the most commonly used among lowereukaryotic host microorganisms. However, a number of other genera,species, and strains are commonly available and useful herein, such asSchizosaccharomyces pombe; Kluyveromyces hosts such as, e.g., K. lactis,K. fragilis (ATCC 12,424), K. bulgaricus (ATCC 16,045), K. wickeramii(ATCC 24,178), K. waltii (ATCC 56,500), K. drosophilarum (ATCC 36,906),K. thermotolerans, and K. marxianus; yarrowia (EP 402,226); Pichiapastoris (EP 183,070); Candida; Trichoderma reesia (EP 244,234);Neurospora crassa; Schwanniomyces such as Schwanniomyces occidentalis;and filamentous fungi such as, e.g., Neurospora, Penicillium,Tolypocladium, and Aspergillus hosts such as A. nidulans and A. niger.

Suitable host cells for the expression of glycosylated anti-sphingolipidantibodies are derived from multicellularorganisms. Examples ofinvertebrate cells include plant and insect cells. Numerous baculoviralstrains and variants and corresponding permissive insect host cells fromhosts such as Spodoptera frugiperda (caterpillar), Aedes aegypti(mosquito), Aedes albopictus (mosquito), Drosophila melanogaster(fruitfly), and Bombyx mori have been identified. A variety of viralstrains for transfection are publicly available, e.g., the L-1 variantof Autographa californica NPV and the Bm-5 strain of Bombyx mori NPV,and such viruses may be used as the virus herein according to thepresent invention, particularly for transfection of Spodopterafrugiperda cells. Plant cell cultures of cotton, corn, potato, soybean,petunia, tomato, and tobacco can also be utilized as hosts.

However, interest has been greatest in vertebrate cells, and propagationof vertebrate cells in culture (tissue culture) has become a routineprocedure. Examples of useful mammalian host cell lines are monkeykidney CV1 line transformed by SV40 (COS-7, ATCC CRL 1651); humanembryonic kidney line (293 or 293 cells subcloned for growth insuspension culture, Graham, et al., J. Gen Virol. 36:59 (1977)); babyhamster kidney cells (BHK, ATCC CCL 10); Chinese hamster ovarycells/-DHFR (CHO, Urlaub, et al., Proc. Natl. Acad. Sci. USA 77:4216(1980)); mouse Sertoli cells (TM4, Mather, Biol. Reprod. 23:243-251(1980)); monkey kidney cells (CV1 ATCC CCL 70); African green monkeykidney cells (VERO-76, ATCC CRL-1587); human cervical carcinoma cells(HELA, ATCC CCL 2); canine kidney cells (MDCK, ATCC CCL 34); buffalo ratliver cells (BRL 3A, ATCC CRL 1442); human lung cells (WI38, ATCC CCL75); human liver cells (Hep G2, HB 8065); mouse mammary tumor (MMT060562, ATCC CCL51); TRI cells (Mather, et al., Annals N.Y. Acad. Sci.383:44-68 (1982)); MRC 5 cells; FS4 cells; and a human hepatoma line(Hep G2).

Host cells are transformed with the above-described expression orcloning vectors for anti-sphingolipid antibody production and culturedin conventional nutrient media modified as appropriate for inducingpromoters, selecting transformants, or amplifying the genes encoding thedesired sequences.

The host cells used to produce the anti-sphingolipid antibody of thisinvention may be cultured in a variety of media. Commercially availablemedia such as Ham's F10 (Sigma), Minimal Essential Medium ((MEM),(Sigma), RPMI-1640 (Sigma), and Dulbecco's Modified Eagle's Medium((DMEM), Sigma) are suitable for culturing the host cells. In addition,any of the media described in Ham, et al., Meth. Enz. 58:44 (1979),Barnes, et al., Anal. Biochem.102:255 (1980), U.S. Pat. Nos. 4,767,704;4,657,866; 4,927,762; 4,560,655; or 5,122,469; WO 90/03430; WO 87/00195;or U.S. Pat. Re. 30,985 may be used as culture media for the host cells.Any of these media may be supplemented as necessary with hormones and/orother growth factors (such as insulin, transferrin, or epidermal growthfactor), salts (such as sodium chloride, calcium, magnesium, andphosphate), buffers (such as HEPES), nucleotides (such as adenosine andthymidine), antibiotics (such as GENTAMYCIN™ drug), trace elements(defined as inorganic compounds usually present at final concentrationsin the micromolar range), and glucose or an equivalent energy source.Any other necessary supplements may also be included at appropriateconcentrations that would be known to those skilled in the art. Theculture conditions, such as temperature, pH, and the like, are thosepreviously used with the host cell selected for expression, and will beapparent to the ordinarily skilled artisan.

When using recombinant techniques, the antibody can be producedintracellularly, in the periplasmic space, or directly secreted into themedium. If the antibody is produced intracellularly, as a first step,the particulate debris, either host cells or lysed fragments, isremoved, for example, by centrifugation or ultrafiltration. Carter, etal., Bio/Technology 10:163-167 (1992) describe a procedure for isolatingantibodies that are secreted to the periplasmic space of E. coli.Briefly, cell paste is thawed in the presence of sodium acetate (pH3.5), EDTA, and phenylmethylsulfonylfluoride (PMSF) over about 30 min.Cell debris can be removed by centrifugation. Where the antibody issecreted into the medium, supernatants from such expression systems aregenerally first concentrated using a commercially available proteinconcentration filter, for example, an Amicon or Millipore Pelliconultrafiltration unit. A protease inhibitor such as PMSF may be includedin any of the foregoing steps to inhibit proteolysis and antibiotics maybe included to prevent the growth of adventitious contaminants.

The antibody composition prepared from the cells can be purified using,for example, hydroxylapatite chromatography, gel electrophoresis,dialysis, and affinity chromatography, with affinity chromatographybeing the preferred purification technique. The suitability of protein Aas an affinity ligand depends on the species and isotype of anyimmunoglobulin Fc domain that is present in the antibody. Protein A canbe used to purify antibodies that are based on human heavy chains(Lindmark, et al., J. Immunol. Meth. 62:1-13 (1983)). Protein G isrecommended for all mouse isotypes and for human y3 (Guss, et al., EMBOJ. 5:15671575 (1986)). The matrix to which the affinity ligand isattached is most often agarose, but other matrices are available.Mechanically stable matrices such as controlled pore glass orpoly(styrenedivinyl)benzene allow for faster flow rates and shorterprocessing times than can be achieved with agarose. Where the antibodycomprises a CH3 domain, the Bakerbond ABX™ resin (J. T. Baker,Phillipsburg, N.J.) is useful for purification. Other techniques forprotein purification, such as fractionation on an ion-exchange column,ethanol precipitation, Reverse Phase HPLC, chromatography on silica,chromatography on heparin SEPHAROSE™, chromatography on an anion orcation exchange resin (such as a polyaspartic acid column),chromatofocusing, SDS-PAGE, and ammonium sulfate precipitation are alsoavailable depending on the antibody to be recovered.

Following any preliminary purification step(s), the mixture comprisingthe antibody of interest and contaminants may be subjected to low pHhydrophobic interaction chromatography using an elution buffer at a pHbetween about 2.5-4.5, preferably performed at low salt concentrations(e.g., from about 0-0.25M salt).

C. Pharmaceutical Formulations

Therapeutic formulations of an antibody or immune-derived moiety of theinvention are prepared for storage by mixing the antibody having thedesired degree of purity with optional physiologically acceptablecarriers, excipients, or stabilizers (see, e.g., Remington'sPharmaceutical Sciences 16th edition, Osol, A. Ed. (1980)), in the formof lyophilized formulations or aqueous solutions. Acceptable carriers,excipients, or stabilizers are nontoxic to recipients at the dosages andconcentrations employed, and include buffers such as phosphate, citrate,and other organic acids; antioxidants including ascorbic acid andmethionine; preservatives (such as octadecyldimethylbenzyl ammoniumchloride; hexamethonium chloride; benzalkonium chloride, benzethoniumchloride; phenol, butyl or benzyl alcohol; alkyl parabens such as methylor propyl paraben; catechol; resorcinol; cyclohexanol; 3-pentanol; andm-cresol); low molecular weight (less than about 10 residues)polypeptides; proteins, such as serum albumin, gelatin, orimmunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone;amino acids such as glycine, glutamine, asparagine, histidine, arginine,or lysine; monosaccharides, disaccharides, and other carbohydratesincluding glucose, mannose, or dextrins; chelating agents such as EDTA;sugars such as sucrose, mannitol, trehalose or sorbitol; salt-formingcounter-ions such as sodium; metal complexes (e.g., Zn-proteincomplexes); and/or non-ionic surfactants such as TWEEN™, PLURONICS™ orpolyethylene glycol (PEG).

The formulation herein may also contain more than one active compound asnecessary for the particular indication being treated, preferably thosewith complementary activities that do not adversely affect each other.Such molecules are suitably present in combination in amounts that areeffective for the purpose intended.

The active ingredients may also be entrapped in microcapsule prepared,for example, by coacervation techniques or by interfacialpolymerization, for example, hydroxymethylcellulose orgelatin-microcapsule and poly-(methylmethacylate) microcapsule,respectively, in colloidal drug delivery systems (for example,liposomes, albumin microspheres, microemulsions, nano-particles andnanocapsules) or in macroemulsions. Such techniques are disclosed inRemington's Pharmaceutical Sciences, 16th edition, Osol, A. Ed. (1980).

The formulations to be used for in vivo administration must be sterile.This is readily accomplished for instance by filtration through sterilefiltration membranes.

Sustained-release preparations may be prepared. Suitable examples ofsustained-release preparations include semipermeable matrices of solidhydrophobic polymers containing the antibody, which matrices are in theform of shaped articles, e.g., films, or microcapsule. Examples ofsustained-release matrices include polyesters, hydrogels (for example,poly(2-hydroxyethyl-methacrylate), or poly(vinyl alcohol)), polylactides(U.S. Pat. No. 3,773,919), copolymers of L-glutamic acid andy-ethyl-L-glutamate, non-degradable ethylene-vinyl acetate, degradablelactic acid-glycolic acid copolymers such as the Lupron Depot™(injectable microspheres composed of lactic acid-glycolic acid copolymerand leuprolide acetate), and poly-D-(−)-3-hydroxybutyric acid. Whilepolymers such as ethylene-vinyl acetate and lactic acid-glycolic acidenable release of molecules for over 100 days, certain hydrogels releaseproteins for shorter time periods. When encapsulated antibodies remainin the body for a long time, they may denature or aggregate as a resultof exposure to moisture at 37° C., resulting in a loss of biologicalactivity and possible changes in immunogenicity. Rational strategies canbe devised for stabilization depending on the mechanism involved. Forexample, if the aggregation mechanism is discovered to be intermolecularS—S bond formation through thio-disulfide interchange, stabilization maybe achieved by modifying sulfhydryl residues, lyophilizing from acidicsolutions, controlling moisture content, using appropriate additives,and developing specific polymer matrix compositions.

A preferred formulation for systemic administration of the antibodies ofthe invention is disclosed in provisional patent application U.S.61/042,736, “Pharmaceutical Compositions for BindingSphingosine-1-Phosphate”, filed Apr. 5, 2008, and commonly owned withthe instant invention. This formulation is described in Example 30hereinbelow.

D. Non-Therapeutic Uses for the Antibodies

The antibodies of the invention may be used as affinity purificationagents. In this process, the antibodies are immobilized on a solid phasesuch a Sephadex resin or filter paper, using methods well known in theart. The immobilized antibody is contacted with a sample containing thesphingolipid to be purified, and thereafter the support is washed with asuitable solvent that will remove substantially all the material in thesample except the sphingolipid, which is bound to the immobilizedantibody. Finally, the support is washed with another suitable solvent,such as glycine buffer, for instance between pH 3 to pH 5.0, that willrelease the sphingolipid from the antibody.

Anti-sphingolipid antibodies may also be useful in diagnostic assays forsphingolipid, e.g., detecting its expression in specific cells, tissues(such as biopsy samples), or bodily fluids. Such diagnostic methods maybe useful in diagnosis of a cardiovascular or cerebrovascular disease ordisorder.

For diagnostic applications, the antibody typically will be labeled witha detectable moiety. Numerous labels are available which can begenerally grouped into the following categories:

(a) Radioisotopes, such as ³⁵S, ¹⁴C, ¹²⁵I, ³H, and ¹³¹I. The antibodycan be labeled with the radioisotope using the techniques described inCurrent Protocols in Immunology, Volumes 1 and 2, Coligen et al., Ed.Wiley-Interscience, New York, N.Y., Pubs. (1991), for example, andradioactivity can be measured using scintillation counting.

(b) Fluorescent labels such as rare earth chelates (europium chelates)or fluorescein and its derivatives, rhodamine and its derivatives,dansyl, Lissamine, phycoerythrin and Texas Red are available. Thefluorescent labels can be conjugated to the antibody using thetechniques disclosed in Current Protocols in Immunology, supra, forexample. Fluorescence can be quantified using a fluorimeter.

(c) Various enzyme-substrate labels are available. For example, U.S.Pat. No. 4,275,149 provides a review of some of these. The enzymegenerally catalyzes a chemical alteration of the chromogenic substratethat can be measured using various techniques. For example, the enzymemay catalyze a color change in a substrate, which can be measuredspectrophotometrically. Alternatively, the enzyme may alter thefluorescence or chemiluminescence of the substrate. Techniques forquantifying a change in fluorescence are described above. Thechemiluminescent substrate becomes electronically excited by a chemicalreaction and may then emit light that can be measured (using achemiluminometer, for example) or donates energy to a fluorescentacceptor. Examples of enzymatic labels include luciferases (e.g.,firefly luciferase and bacterial luciferase; U.S. Pat. No. 4,737,456),luciferin, 2,3-dihydrophthalazinediones, malate dehydrogenase, urease,peroxidase such as horseradish peroxidase (HRPO), alkaline phosphatase,beta-galactosidase, glucoamylase, lysozyme, saccharide oxidases (e.g.,glucose oxidase, galactose oxidase, and glucose-6-phosphatedehydrogenase), heterocyclicoxidases (such as uricase and xanthineoxidase), lactoperoxidase, microperoxidase, and the like. Techniques forconjugating enzymes to antibodies are described in O'Sullivan, et al.,Methods for the Preparation of Enzyme-Antibody Conjugates for use inEnzyme Immunoassay, in Methods in Enzym. (ed J. Langone & H. VanVunakis), Academic press, New York, 73:147-166 (1981).

Examples of enzyme-substrate combinations include, for example:

(i) Horseradish peroxidase (HRPO) with hydrogen peroxidase as asubstrate, wherein the hydrogen peroxidase oxidizes a dye precursor(e.g., orthophenylene diamine (OPD) or 3,3′,5,5′-tetramethyl benzidinehydrochloride (TMB));

(ii) alkaline phosphatase (AP) with para-Nitrophenyl phosphate aschromogenic substrate; and (iii) β-D-galactosidase (β-D-Gal) with achromogenic substrate (e.g., p-nitrophenyl-β-D-galactosidase) orfluorogenic substrate 4-methylumbelliferyl-β-D-galactosidase.

Numerous other enzyme-substrate combinations are available to thoseskilled in the art. For a general review of these, see U.S. Pat. Nos.4,275,149 and 4,318,980.

Sometimes, the label is indirectly conjugated with the antibody. Theskilled artisan will be aware of various techniques for achieving this.For example, the antibody can be conjugated with biotin and any of thethree broad categories of labels mentioned above can be conjugated withavidin, or vice versa. Biotin binds selectively to avidin and thus, thelabel can be conjugated with the antibody in this indirect manner.Alternatively, to achieve indirect conjugation of the label with theantibody, the antibody is conjugated with a small hapten (e.g., digoxin)and one of the different types of labels mentioned above is conjugatedwith an anti-hapten antibody (e.g., anti-digoxin antibody). Thus,indirect conjugation of the label with the antibody can be achieved.

In another embodiment of the invention, the anti-sphingolipid antibodyneed not be labeled, and the presence thereof can be detected using alabeled antibody which binds to the anti-sphingolipid antibody.

The antibodies of the present invention may be employed in any knownassay method, such as competitive binding assays, direct and indirectsandwich assays, and immunoprecipitation assays. See, e.g., Zola,Monoclonal Antibodies: A Manual of Techniques, pp.147-158 (CRC Press,Inc. 1987).

Competitive binding assays rely on the ability of a labeled standard tocompete with the test sample analyte for binding with a limited amountof antibody. The amount of sphingolipid in the test sample is inverselyproportional to the amount of standard that becomes bound to theantibodies. To facilitate determining the amount of standard thatbecomes bound, the antibodies generally are insoluble before or afterthe competition, so that the standard and analyte that are bound to theantibodies may conveniently be separated from the standard and analytethat remain unbound.

Sandwich assays involve the use of two antibodies, each capable ofbinding to a different immunogenic portion, or epitope, of the proteinto be detected. In a sandwich assay, the test sample analyte is bound bya first antibody that is immobilized on a solid support, and thereaftera second antibody binds to the analyte, thus forming an insolublethree-part complex. See, e.g., U.S. Pat. No. 4,376,110. The secondantibody may itself be labeled with a detectable moiety (direct sandwichassays) or may be measured using an anti-immunoglobulin antibody that islabeled with a detectable moiety (indirect sandwich assay). For example,one type of sandwich assay is an ELISA assay, in which case thedetectable moiety is an enzyme.

For immunohistochemistry, the blood or tissue sample may be fresh orfrozen or may be embedded in paraffin and fixed with a preservative suchas formalin, for example.

The antibodies may also be used for in vivo diagnostic assays.Generally, the antibody is labeled with a radionuclide (such as ¹¹¹In,⁹⁹Tc, ¹⁴C, ¹³¹I, ¹²⁵I, ³H, ³²P, or ³⁵S) so that the bound targetmolecule can be localized using immunoscintillography.

E. Diagnostic Kits

As a matter of convenience, the antibody of the present invention can beprovided in a kit, for example, a packaged combination of reagents inpredetermined amounts with instructions for performing the diagnosticassay. Where the antibody is labeled with an enzyme, the kit willinclude substrates and cofactors required by the enzyme (e.g., asubstrate precursor which provides the detectable chromophore orfluorophore). In addition, other additives may be included such asstabilizers, buffers (e.g., a block buffer or lysis buffer) and thelike. The relative amounts of the various reagents may be varied widelyto provide for concentrations in solution of the reagents whichsubstantially optimize the sensitivity of the assay. Particularly, thereagents may be provided as dry powders, usually lyophilized, includingexcipients which on dissolution will provide a reagent solution havingthe appropriate concentration.

F. Therapeutic Uses for the Antibody

For therapeutic applications, the anti-sphingolipid antibodies of theinvention are administered to a mammal, preferably a human, in apharmaceutically acceptable dosage form such as those discussed above,including those that may be administered to a human intravenously as abolus or by continuous infusion over a period of time, by intramuscular,intraperitoneal, intra-cerebrospinal, subcutaneous, intra-articular,intrasynovial, intrathecal, oral, topical, or inhalation routes.

For the prevention or treatment of disease, the appropriate dosage ofantibody will depend on the type of disease to be treated, as definedabove, the severity and course of the disease, whether the antibody isadministered for preventive or therapeutic purposes, previous therapy,the patient's clinical history and response to the antibody, and thediscretion of the attending physician. The antibody is suitablyadministered to the patient at one time or over a series of treatments.

Depending on the type and severity of the disease, about 1 ug/kg toabout 50 mg/kg (e.g., 0.1-20 mg/kg) of antibody is an initial candidatedosage for administration to the patient, whether, for example, by oneor more separate administrations, or by continuous infusion. A typicaldaily or weekly dosage might range from about 1 μg/kg to about 20 mg/kgor more, depending on the factors mentioned above. For repeatedadministrations over several days or longer, depending on the condition,the treatment is repeated until a desired suppression of diseasesymptoms occurs. However, other dosage regimens may be useful. Theprogress of this therapy is easily monitored by conventional techniquesand assays, including, for example, radiographic imaging.

According to another embodiment of the invention, the effectiveness ofthe antibody in preventing or treating disease may be improved byadministering the antibody serially or in combination with another agentthat is effective for those purposes, such as chemotherapeuticanti-cancer drugs, for example. Such other agents may be present in thecomposition being administered or may be administered separately. Theantibody is suitably administered serially or in combination with theother agent.

G. Articles of Manufacture

In another embodiment of the invention, an article of manufacturecontaining materials useful for the treatment of the disorders describedabove is provided. The article of manufacture comprises a container anda label. Suitable containers include, for example, bottles, vials,syringes, and test tubes. The containers may be formed from a variety ofmaterials such as glass or plastic. The container holds a compositionwhich is effective for treating the condition and may have a sterileaccess port (for example the container may be an intravenous solutionbag or a vial having a stopper pierceable by a hypodermic injectionneedle). The active agent in the composition is the anti-sphingolipidantibody. The label on, or associated with, the container indicates thatthe composition is used for treating the condition of choice. Thearticle of manufacture may further comprise a second containercomprising a pharmaceutically-acceptable buffer, such asphosphate-buffered saline, Ringer's solution and dextrose solution. Itmay further include other materials desirable from a commercial and userstandpoint, including other buffers, diluents, filters, needles,syringes, and package inserts with instructions for use.

The invention will be better understood by reference to the followingExamples, which are intended to merely illustrate the best mode nowknown for practicing the invention. The scope of the invention is not tobe considered limited thereto.

Examples Example 1 Murine Monoclonal Antibody to S1P (Sphingomab™;LT1002)

One type of therapeutic antibody specifically binds undesirablesphingolipids to achieve beneficial effects such as, e.g., (1) loweringthe effective concentration of undesirable, toxic sphingolipids (and/orthe concentration of their metabolic precursors) that would promote anundesirable effect such as a cardiotoxic, tumorigenic, or angiogeniceffect; (2) to inhibit the binding of an undesirable, toxic,tumorigenic, or angiogenic sphingolipids to a cellular receptortherefore, and/or to lower the concentration of a sphingolipid that isavailable for binding to such a receptor. Examples of such therapeuticeffects include, but are not limited to, the use of anti-S1P antibodiesto lower the effective in vivo serum concentration of available S1P,thereby blocking or at least limiting S1P's tumorigenic and angiogeniceffects and its role in post-MI heart failure, cancer, or fibrongenicdiseases.

Thiolated S1P was synthesized to contain a reactive group capable ofcross-linking the essential structural features of S1P to a carriermolecule such as KLH. Prior to immunization, the thio-S1P analog wasconjugated via IOA or SMCC cross-linking to protein carriers (e.g., KLH)using standard protocols. SMCC is a heterobifunctional crosslinker thatreacts with primary amines and sulfhydryl groups, and represents apreferred crosslinker.

Swiss Webster or BALB-C mice were immunized four times over a two monthperiod with 50 μg of immunogen (SMCC facilitated conjugate ofthiolated-S1P and KLH) per injection. Serum samples were collected twoweeks after the second, third, and fourth immunizations and screened bydirect ELISA for the presence of anti-S1P antibodies. Spleens fromanimals that displayed high titers of the antibody were subsequentlyused to generate hybridomas per standard fusion procedures. Theresulting hybridomas were grown to confluency, after which the cellsupernatant was collected for ELISA analysis. Of the 55 mice that wereimmunized, 8 were good responders, showing significant serum titers ofantibodies reactive to S1P. Fusions were subsequently carried out usingthe spleens of these mice and myeloma cells according to establishedprocedures. The resulting 1,500 hybridomas were then screened by directELISA, yielding 287 positive hybridomas. Of these 287 hybridomasscreened by direct ELISA, 159 showed significant titers. Each of the 159hybridomas was then expanded into 24-well plates. The cell-conditionedmedia of the expanded hybridomas were then re-screened to identifystable hybridomas capable of secreting antibodies of interest.Competitive ELISAs were performed on the 60 highest titer stablehybridomas.

Of the 55 mice and almost 1,500 hybridomas screened, one hybridoma wasdiscovered that displayed performance characteristics that justifiedlimited dilution cloning, as is required to ultimately generate a truemonoclonal antibody. This process yielded 47 clones, the majority ofwhich were deemed positive for producing S1P antibodies. Of these 47clones, 6 were expanded into 24-well plates and subsequently screened bycompetitive ELISA. From the 4 clones that remained positive, one waschosen to initiate large-scale production of the S1P monoclonalantibody. SCID mice were injected with these cells and the resultingascites was protein A-purified (50% yield) and analyzed for endotoxinlevels (<3 EU/mg). For one round of ascites production, 50 mice wereinjected, producing a total of 125 mL of ascites. The antibodies wereisotyped as IgG1 kappa, and were deemed >95% pure by HPLC. The antibodywas prepared in 20 mM sodium phosphate with 150 mM sodium chloride (pH7.2) and stored at −70° C. This antibody is designated LT1002 orSphingomab™.

The positive hybridoma clone (designated as clone 306D326.26) wasdeposited with the ATCC (safety deposit storage number SD-5362), andrepresents the first murine mAb directed against S1P. The clone alsocontains the variable regions of the antibody heavy and light chainsthat could be used for the generation of a “humanized” antibody variant,as well as the sequence information needed to construct a chimericantibody.

Screening of serum and cell supernatant for S1P-specific antibodies wasby direct ELISA using a thiolated S1P analog as the antigen. A standardELISA was performed, as described below, except that 50 ul of sample(serum or cell supernatant) was diluted with an equal volume of PBS/0.1%Tween-20 (PBST) during the primary incubation. ELISAs were performed in96-well high binding ELISA plates (Costar) coated with 0.1 μg ofchemically-synthesized thiolated-S1P conjugated to BSA in binding buffer(33.6 mM Na₂CO₃, 100 mM NaHCO₃; pH 9.5). The thiolated-S1P-BSA wasincubated at 37° C. for 1 hr. at 4° C. overnight in the ELISA platewells. The plates were then washed four times with PBS (137 mM NaCl,2.68 mM KCl, 10.14 mM Na₂HPO₄, 1.76 mM KH₂PO₄; pH 7.4) and blocked withPBST for 1 hr. at room temperature. For the primary incubation step, 75uL of the sample (containing the S1P to be measured), was incubated with25 uL of 0.1 ug/mL anti-S1P mAb diluted in PBST and added to a well ofthe ELISA plate. Each sample was performed in triplicate wells.Following a 1 hr. incubation at room temperature, the ELISA plates werewashed four times with PBS and incubated with 100 ul per well of 0.1ug/mL HRP goat anti-mouse secondary (Jackson Immunoresearch) for 1 hr.at room temperature. Plates were then washed four times with PBS andexposed to tetramethylbenzidine (Sigma) for 1-10 minutes. The detectionreaction was stopped by the addition of an equal volume of 1M H₂SO₄.Optical density of the samples was determined by measurement at 450 nmusing an EL-X-800 ELISA plate reader (Bio-Tech).

For cross reactivity, a competitive ELISA was performed as describedabove, except for the following alterations. The primary incubationconsisted of the competitor (S1P, SPH, LPA, etc.) and abiotin-conjugated anti-S1P mAb. Biotinylation of the purified monoclonalantibody was performed using the EZ-Link Sulfo-NHS-Biotinylation kit(Pierce). Biotin incorporation was determined as per kit protocol andranged from 7 to 11 biotin molecules per antibody. The competitor wasprepared as follows: lipid stocks were sonicated and dried under argonbefore reconstitution in DPBS/BSA [1 mg/ml fatty acid free BSA(Calbiochem) in DPBS (Invitrogen 14040-133)]. Purified anti-S1P mAb wasdiluted as necessary in PBS/0.5% Triton X-100. Competitor and antibodysolutions were mixed together so to generate 3 parts competitor to 1part antibody. A HRP-conjugated streptavidin secondary antibody (JacksonImmunoresearch) was used to generate signal.

Another aspect of the competitive ELISA data (shown in FIG. 1, panel A)is that it shows that the anti-S1P mAb was unable to distinguish thethiolated-S1P analog from the natural S1P that was added in thecompetition experiment. It also demonstrates that the antibody does notrecognize any oxidation products since the analog was constructedwithout any double bonds. The anti-S1P mAb was also tested againstnatural product containing the double bond that was allowed to sit atroom temperature for 48 hours. Reverse phase HPLC of the natural S1P wasperformed according to methods reported previously (Deutschman, et al.(July 2003), Am Heart J., vol. 146(1):62-8), and the results showed nodifference in retention time. Further, a comparison of the bindingcharacteristics of the monoclonal antibody to the various lipids shownin FIG. 1, panel A, indicates that the epitope recognized by theantibody do not involve the hydrocarbon chain in the region of thedouble bond of natural S1P. On the other hand, the epitope recognized bythe monoclonal antibody is the region containing the amino alcohol onthe sphingosine base backbone plus the free phosphate. If the freephosphate is linked with a choline (as is the case with SPC), then thebinding was somewhat reduced. If the amino group is esterfied to a fattyacid (as is the case with C1P), no antibody binding was observed. If thesphingosine amino alcohol backbone was replaced by a glycerol backbone(as is the case with LPA), there the S1P-specific monoclonal exhibitedno binding. These epitope mapping data indicate that there is only oneepitope on S1P recognized by the monoclonal antibody, and that thisepitope is defined by the unique polar headgroup of S1P.

In a similar experiment using ELISA measurements, suitable controlmaterials were evaluated to ensure that this anti-S1P monoclonalantibody did not recognize either the protein carrier or thecrosslinking agent. For example, the normal crosslinker SMCC wasexchanged for IOA in conjugating the thiolated-S1P to BSA as the laydownmaterial in the ELISA. When IOA was used, the antibody's bindingcharacteristics were nearly identical to when BSA-SMCC-thiolated-S1P wasused. Similarly, KLH was exchanged for BSA as the protein that wascomplexed with thiolated-S1P as the laydown material. In thisexperiment, there was also no significant difference in the bindingcharacteristics of the antibody.

Binding kinetics: The binding kinetics of S1P to its receptor or othermoieties has, traditionally, been problematic because of the nature oflipids. Many problems have been associated with the insolubility oflipids. For BIAcore measurements, these problems were overcome bydirectly immobilizing S1P to a BIAcore chip. Antibody was then flowedover the surface of the chip and alterations in optical density weremeasured to determine the binding characteristics of the antibody toS1P. To circumvent the bivalent binding nature of antibodies, S1P wascoated on the chip at low densities. Additionally, the chip was coatedwith various densities of S1P (7, 20, and 1000 RU) and antibody bindingdata was globally fit to a 1:1 interaction model. The results shown inFIG. 2 demonstrate the changes in optical density due to the binding ofthe monoclonal antibody to S1P at three different densities of S1P.Overall, the affinity of the monoclonal antibody to S1P was determinedto be very high, in the range of approximately 88 picomolar (pM) to 99nM, depending on whether a monovalent or bivalent binding model was usedto analyze the binding data.

Example 2 ELISA Assays

1. Quantitative ELISAs

Microtiter ELISA plates (Costar, Cat No. 3361) were coated with rabbitanti-mouse IgG, F(ab′)₂ fragment specific antibody (Jackson,315-005-047) diluted in 1M Carbonate Buffer (pH 9.5) at 37° C. for 1 h.Plates were washed with PBS and blocked with PBS/BSA/Tween-20 for 1 hrat 37° C. For the primary incubation, dilutions of non-specific mouseIgG or human IgG, whole molecule (used for calibration curve) andsamples to be measured were added to the wells. Plates were washed andincubated with 100 ul per well of HRP conjugated goat anti-mouse (H+L)diluted 1:40,000 (Jackson, cat No 115-035-146) for 1 hr at 37° C. Afterwashing, the enzymatic reaction was detected with tetramethylbenzidine(Sigma, cat No T0440) and stopped by adding 1 M H₂SO₄. The opticaldensity (OD) was measured at 450 nm using a Thermo Multiskan EX. Rawdata were transferred to GraphPad software for analysis.

2. Direct ELISAs

Microtiter ELISA plates (Costar, Cat No. 3361) were coated with LPA-BSAdiluted in 1M Carbonate Buffer (pH 9.5) at 37° C. for 1 h. Plates werewashed with PBS (137 mM NaCl, 2.68 mM KCl, 10.1 mM Na₂HPO₄, 1.76 mMKH₂PO₄; pH 7.4) and blocked with PBS/BSA/Tween-20 for 1 h at roomtemperature or overnight at 4° C. The samples to be tested were dilutedat 0.4 ug/mL, 0.2 ug/mL, 0.1 ug/mL, 0.05 ug/mL, 0.0125 ug/mL, and 0ug/mL and 100 ul added to each well. Plates were washed and incubatedwith 100 ul per well of HRP conjugated goat anti-mouse (1:20,000dilution) (Jackson, cat. no. 115-035-003) for 1 h at room temperature.After washing, the enzymatic reaction was detected withtetramethylbenzidine (Sigma, cat. no. T0440) and stopped by adding 1 MH₂SO₄. The optical density (OD) was measured at 450 nm using a ThermoMultiskan EX. Raw data were transferred to GraphPad software foranalysis.

3. Competition Assays

The specificity of mAbs was tested in ELISA assays. Microtiter platesELISA plates (Costar, Cat No. 3361) were coated with 18:0 LPA-BSAdiluted in 1M Carbonate Buffer (pH 9.5) at 37° C. for 1 h. Plates werewashed with PBS (137 mM NaCl, 2.68 mM KCl, 10.1 mM Na₂HPO₄, 1.76 mMKH₂PO₄; pH 7.4) and blocked with PBS/BSA/Tween-20 at 37° C. for 1 h orovernight at room temperature. For the primary incubation 0.4 ug/mLanti-LPA mAb and designated amounts of(14:0, 16:0, 18:0, 18:1, 18:2 and20:4) LPA, DSPA, 18:1 LPC (lysophosphatidylcholine), S1P, ceramide andceramide-1-phosphate were added to wells of the ELISA plates andincubated at 37° C. for 1 h. Plates were washed and incubated with 100ul per well of HRP conjugated goat anti-mouse (1:20,000 dilution)(Jackson, cat No 115-035-003) or HRP conjugated goat anti-human(H+L)diluted 1:50,000 (Jackson, cat No 109-035-003) at 37° C. for 1 h. Afterwashing, the enzymatic reaction was detected with tetramethylbenzidineand stopped by adding 1 M H₂SO₄. The optical density (OD) was measuredat 450 nm using a Thermo Multiskan EX. Raw data were transferred toGraphPad software for analysis.

Example 3 SPHINGOMAB Murine mAb is Highly Specific for S1P

A competitive ELISA demonstrates SPHINGOMAB's specificity for S1Pcompared to other bioactive lipids. SPHINGOMAB demonstrated nocross-reactivity to sphingosine (SPH), the immediate metabolic precursorof S1P or lysophosphatidic acid (LPA), an important extracellularsignaling molecule that is structurally and functionally similar to S1P.SPHINGOMAB did not recognize other structurally similar lipids andmetabolites, including ceramide-1-phosphate (C1P), dihydrosphingosine(DH-SPH), phosphatidyl serine (PS), phosphatidyl ethanolamine (PE), orsphingomyelin (SM). SPHINGOMAB did cross react withdihydrosphingosine-1-phosphate (DH-S1P) and, to a lesser extent,sphingosylphorylcholine (SPC) (FIG. 3).

Example 4 SPHINGOMAB Significantly Reduces CNV and Scar Formation in aMurine Model of CNV

Female C57BL6/J mice were subjected to laser-induced rupture of Bruch'smembrane and administered either 0.5 μg of Sphingomab or anisotype-matched non-specific (NS) antibody diluted in 2 μl ofphysiological saline. Mice were sacrificed 14 and 28 days after laserrupture.

To induce CNV lesions, the pupils were dilated with ophthalmictropicamide (0.5%) and phenylephrine (2.5%). A coverslip was placed onthe eye. An Oculight GL 532 nm (Iridex Corporation, Mountain View,Calif.) coupled to a slit lamp set to deliver a 100 msec pulse at 150 mWwith a 50 μm spot size was used to rupture Bruch's membrane in threequadrants of the right eye located approximately 50 μm from the opticdisc at relative 9, 12 and 3 o'clock positions. The left eye served asan uninjured control in all cases. Any lesion not associated with avapor bubble or lesions that became confluent were excluded fromanalysis.

To measure CNV lesion size, choroidal flatmounts of thesclera-choroid-RPE complex were prepared and stained for vasculature (R.communis agglutinin I; red) and pericytes (CD 140b; green). Digitalimages were captured using an epifluorescence Zeiss Axioplan 2 with RGBSpot high-resolution digital camera and laser scanning confocalmicroscope (BioRad MRC 1024, BioRad Corporation, Temecula, Calif.). Forvolumetric analysis, a z-series capture was used and the sum of lesionarea throughout the z-series was multiplied by the z thickness (4 μm) toobtain the lesion volume.

To assess collagen deposition, the sclera-choroid-RPE complex wasstained with Masson's Trichrome. The sclera-choroid-RPE complex wasembedded in paraffin and then serially sectioned at a thickness of 6microns. Approximately 30 sections per lesion were evaluated.Quantitation of the volume of collagen deposition was calculated in thesame manner as described for CNV lesion volume.

Captured digital images were evaluated morphometrically using ImageJsoftware (Research Services Branch, National Institutes of Health,Bethesda, Md.). FIG. 4A shows that SPHINGOMAB dramatically attenuateschoroidal neovascularization 14 and 28 days after laser-induced ruptureof Bruch's membrane. FIG. 4B shows that SPHINGOMAB significantly reducesfibrosis associated with CNV lesion formation 28 days afterlaser-induced rupture of Bruch's membrane.

Example 5 SPHINGOMAB Inhibits Neovascularization through MultipleMechanisms Including Inhibition of Endothelial Cell Migration and TubeFormation

S1P promotes the migration of human umbilical vein endothelial cells(HUVECs) and, in Matrigel and other assays, the formation of de novo BVformation in vitro; SPHINGOMAB can neutralize these effects of S1P.Experiments were performed as described by Visentin et al. (Cancer CellMarch 2006; 9(3):225-38). Data in FIG. 5A suggest that HUVECs seededonto GF-reduced Matrigel formed multiple capillary-like structures inthe presence of S1P and failed to form capillary-like structures in theabsence of S1P or when co-incubated with SPHINGOMAB and S1P. Data inFIG. 5B demonstrate the potent ability of 0.1-1 μM S1P to stimulateHUVEC migration 2-2.5 fold over non-treated HUVECs, or HUVECsco-incubated with SPHINGOMAB in a Matrigel chemoinvasion assay.Combined, these studies demonstrate that SPHINGOMAB can efficientlymitigate the pro-angiogenic effects of S1P on ECs.

Example 6 SPHINGOMAB Inhibits Neovascularization through MultipleMechanisms Including Mitigation of the Effects of S1P, VEGF and bFGF InVivo

Based on in vivo studies showing that S1P increased endothelialcapillary growth into subcutaneously implanted Matrigel plugs, wespeculated that SPHINGOMAB could reduce de novo BV formation in vivo. Toinvestigate this, we employed the in vivo Matrigel Plug assay forneovascularization. In one set of experiments, Matrigel was supplementedwith either 1 μM S1P, 0.5 μg/mL bFGF or 1 μg/mL VEGF and then injectedI.P. into mice (n=4). After 10 days, the mice were heparinized andinjected with the fluorescent lectin, Isolectin B4-FITC, which binds toadhesion molecules expressed by vascular EC that form the growing BVs.The plugs were then excised, frozen in OCT, sectioned and viewed forFITC-stained BVs. Data in FIG. 6A suggest that S1P is a more potentstimulator of neovascularization in vivo than bFGF or VEGF [Lee, et al.,(1999), Biochem Biophys Res Commun,. vol 264: 743-50], as evidenced bythe vast amount of FITC-stained BVs in the plugs containing S1P comparedto the plugs containing bFGF or VEGF.

Sections of the plugs were then stained with hemotoxyln & eosin forevaluation of EC infiltration (FIG. 6B). The infiltration of ECs is acritical step in neo-vascularization. Plugs containing S1P had a 3-foldincrease of EC infiltration in comparison to the Matrigel only plugs.Cell infiltration is presumed to be ECs although we recognize that othercell types such as immune cells may also be stained. Mice systemicallyadministered SPHINGOMAB every 48 hrs (initiated 1 day prior to plugimplantation), demonstrated a reduced amount of EC infiltration evenwhen S1P was added to the Matrigel plugs. These results demonstrate theability of SPHINGOMAB to inhibit EC infiltration in vivo.

Endogenous S1P from the blood and surrounding tissue could supply awound with pro-angiogenic stimuli. The ability of SPHINGOMAB to reduceendogenous S1P in a wound was investigated. Optimally stimulated plugs(Matrigel supplemented with 0.5 μg/mL bFGF or 10 mg/mL VEGF) wereimplanted into mice. Mice received i.p. injections of 25 mg/kgSPHINGOMAB or saline every 48 hrs starting 1 day prior to Matrigelimplantation. Each treatment group (Matrigel, Matrigel plus GF orMatrigel plus GF and administered SPHINGOMAB) consisted of a minimum of6 mice. After 10 days, the mice were treated with heparin, injected withIsolectin B4-FITC, the plugs excised, embedded in OCT freezing mediumand sectioned. Micro-vascular density was qualitatively accessed bylectin-FITC stained vessels as shown in FIG. 6C. BV staining wassporadic in control (untreated) plugs, whereas the plugs containing bFGFor VEGF demonstrated significant evidence of vascularization. The plugsfrom mice treated with the SPHINGOMAB demonstrated a significantreduction in BV formation compared to the bFGF or VEGF plugs fromsaline-treated mice. Quantification of stained vessels revealed a 5 to8.5-fold decrease in neovascularization of VEGF- or bFGF-containingplugs, respectively, from animals treated with SPHINGOMAB in comparisonto saline-treated animals (FIG. 6C). This evaluation furtherdemonstrates the ability of endogenous serum and tissue S1P to enhancemicro-vascularization as well as the ability of SPHINGOMAB to neutralizeendogenous S1P's pro-angiogenic effects.

Example 7 SPHINGOMAB Inhibits Scar Formation In Vivo

S1P makes profound contributions to wound healing by activatingfibroblast migration, proliferation and collagen production; SPHINGOMABneutralizes these effects. Several studies using multiple types offibroblasts confirm S1P's ability to promote wound healing: 1) S1Pincreased Swiss-3T3 fibroblast proliferation as measured by ³H-thymidineincorporation using standard methods (FIG. 7A); 2) S1P promoted themigration of cardiac fibroblasts in a standard scratch wound healingassay. (FIG. 7B); 3) S1P promoted collagen expression by cardiacfibroblasts isolated from transgenic mice possessing the collagen 1a GFPreporter, as indicated by immunofluorescence microscopy (FIG. 7C); and4) S1P induced the differentiation of WI-3 8 lung fibroblasts intomyofibroblasts, cells that are active in scar remodeling, as indicatedby increased expression of myofibroblast marker protein, smooth muscleactin, using immunoblot analysis (FIG. 7D). In each of these assays,SPHINGOMAB neutralized S1P's. It is anticipated that ocular fibroblastswould respond similarly to S1P and SPHINGOMAB. Similarities betweencardiovascular disease and neovascular lesions of AMD, including scarremodeling and subsequent, maladaptive fibrous tissue formation, havebeen noted (Vine, et al. (2005), Ophthalmology,. vol 112: 2076-80 andSeddon and Chen (2004), Int Ophthalmol Clin,. vol 44: 17-39); thus, itis believed that SPHINGOMAB would have effects on ocularneovascularization and scarring similar to those it has demonstrated incardiovascular systems.

Studies evaluated the efficacy of SPHINGOMAB to reduce cardiac scarformation after permanent myocardial infarction (MI) via ligation of theleft descending coronary artery in mice. Systemic administration of 25mg/kg SPHINGOMAB or saline was initiated 48 hrs after surgery. Antibodyadministration at 48 hr. was chosen to allow normal, reparative scarformation to occur during the early remodeling phase and permitbeneficial, S1P-stimulated angiogenesis immediately after the MI. Twoweeks after the infarct, mice were sacrificed and fibrosis was accessedby Masson's trichrome staining of the cardiac tissue. Animals receivingSPHINGOMAB treatments exhibited almost complete abrogation ofperivascular fibrosis (FIG. 7, photos). As a control for anynon-specific wound-healing responses, sham animals underwent thoracotomywithout coronary artery ligation (FIG. 7E).

Example 8 S1P Promotes Transformation of Ocular Epithelial Cells andFibroblasts into Contractile, Scar Tissue-Producing Myofibroblasts

Pathological tissue fibrosis (scar formation) is a primary, contributingfactor in a number of ocular disorders, including: age-related maculardegeneration, diabetic retinopathy, retinopathy of prematurity,proliferative vitreoretinopathy and consequences of glaucoma surgery.

In many of these disorders, circulating growth factors and chemokinespromote the transformation of normal ocular cells into fibrocontractile,scar tissue-producing cells that have been termed “myofibroblasts”.Normally, myofibroblasts are responsible for tissue repair as part ofthe wound healing response following injury. However altered number andfunction of myofibroblasts are implicated in diseases characterized bypathological scar tissue formation in the liver, skin, lung, kidney,heart and eyes. In the eye, transformation of retinal pigmentedepithelial (RPE) cells to a myofibroblast phenotype is linked toformation of fibro-contractile membranes which cause retinal detachmentand subsequent vision impairment. In addition, myofibroblasttransformation of ocular fibroblasts can result in abnormal scar tissueproduction after eye injury leading to subsequent vision loss. Althoughmany of the circulating protein factors in the eye that promotemyofibroblast formation have been identified, nothing is known regardingthe role of lysolipids such as S1P in this process. Therefore, weexamined the effects of S1P on myofibroblast transformation of severalhuman ocular cell lines. As shown in FIG. 8, S1P stimulates productionof α-Smooth muscle actin (α-SMA; a myofibroblast marker) in humanretinal pigmented epithelial cells (FIG. 8A) and human conjunctivafibroblasts (FIG. 8B). These data demonstrate for the first time, thatS1P is among the milieu of circulating chemical factors that promotetransformation of ocular epithelial cells and fibroblasts intocontractile, scar tissue-producing myofibroblasts which may contributeto retinal detachment, ocular fibrosis and subsequent vision impairment.

In these experiments, the ability of S1P to promote α-SMA expressiondiffered in a concentration dependent manner between the retinalpigmented epithelial cells and conjunctiva fibroblasts. As shown, asignificant increase in α-SMA expression was observed at the 0.001 μMconcentration in the epithelial cells which then decreased to basallevels at the 10 μM concentration. In contrast, a significant increasein α-SMA expression was observed only at the 10 μM concentration in theconjunctiva fibroblasts. This difference is believed to result fromincreased S1P receptor expression in the epithelial cells compared tothe fibroblasts. Due to increased S1P receptor expression levels,retinal pigmented epithelial cells are likely more sensitive to S1P atlow concentrations. In contrast, at high S1P levels the receptors becomesensitized or possibly even internalized leading to decreasedstimulation by S1P.

Collagen is one of the primary structural proteins that supports alltissues in the body and is one of the main components of scar tissue. Inthe non-pathological setting, total collagen content within tissue ismaintained via a balance between collagen production by fibroblasts anddegradation by certain enzymes. A number of disorders that involveincreased levels of scar tissue result, in part, from physiological andmolecular processes that inhibit degradation of collagen that is needfor scar formation. It was hypothesized that the ability of S1P topromote scar tissue formation may result from its ability to inhibitcollagen degradation, thereby leading to net increases in scar tissuewithin organs. Therefore, the effects of S1P on expression ofplasminogen activator inhibitor (PAI-1) in human conjunctiva fibroblastswere examined. Increased PAI-1 expression correlates with a decrease inthe proteolytic degradation of connective tissue and is upregulated inassociation with several fibrotic diseases that involve increasedscarring. As shown in FIG. 8C, S1P stimulates the PAI-1 expression in adose-dependent manner. These data suggest that, may also promote scartissue formation by stimulating the expression of proteins that inhibitits degradation, suggesting that S1P functions through multiplemechanistic pathways to promote and maintain pathological scarringassociated with ocular diseases.

Example 9 SPHINGOMAB Inhibits Inflammatory and Immune Cell Infiltration

Inflammation is the first response in the remodeling process. It istriggered both by ischemia and by cellular damage and results inup-regulation of cytokine expression which stimulates the migration ofmacrophages and neutrophils to the injured area for phagocytosis of deadcells and to further up-regulate the inflammatory response [Jordan, etal.(1999), Cardiovasc Res,. vol 43: 860-78]. Mast cells are alsoimportant cellular mediators of the inflammatory response. S1P releasedfrom mast cells is responsible for many of the adverse responses seen inexperimental animal models of inflammation [Jolly, et al (2004), J ExpMed,. vol 199: 959-70 and Jolly et al (2005), Blood,. vol 105: 4736-42].

Based upon the similarities of immune and inflammatory responses in CNVand CVD, the efficacy of SPHINGOMAB to mitigate immune cell infiltrationinto a wound was evaluated in a murine infarct model as an indication ofSPHINGOMAB's potential effects in mitigating these damages during AMD[Vine, et al. (2005), Ophthalmology,. vol 112: 2076-80; and Seddon andChen (2004), Int Ophthalmol Clin,. vol 44: 17-39]. Four days post-MI,macrophage and mast cell infiltration was evaluated using MAC-1 andMCG35 antibodies, respectively, within the area at risk. SPHINGOMABdramatically attenuated the density of inflammatory macrophages (FIG.9A) and mast cells (FIG. 9B) suggesting that SPHINGOMAB may neutralizeimmune and inflammatory damages during AMD.

Example 10 Cloning and Characterization of the Variable Domains of anS1P Murine Monoclonal Antibody (LT1002; Sphingomab)

This example reports the cloning of the murine mAb against S1P. Theoverall strategy consisted of cloning the murine variable domains ofboth the light chain (VL) and the heavy chain (VH). The consensussequence of 306D VH shows that the constant region fragment isconsistent with a gamma 2b isotype. The murine variable domains werecloned together with the constant domain of the light chain (CL) andwith the constant domain of the heavy chain (CH1, CH2, and CH3),resulting in a chimeric antibody construct.

1. Cloning of the Murine mAb

A clone from the anti-S1P hybridoma cell line 306D326.1 (ATCC#SD-5362)was grown in DMEM (Dulbecco's Dulbecco's Modified Eagle Medium withGlutaMAX™, 4500 mg/L D-Glucose, Sodium Puruvate; Gibco/Invitrogen,Carlsbad, Calif., 111-035-003), 10% FBS (Sterile Fetal Clone I, PerbioScience), and 1× glutamine/Penicillin/Streptomycin (Gibco/Invitrogen).Total RNA was isolated from 10⁷ hybridoma cells using a procedure basedon the RNeasy Mini kit (Qiagen, Hilden Germany). The RNA was used togenerate first strand cDNA following the manufacturer's protocol (1^(st)strand synthesis kit, Amersham Biosciences).

The immunoglobulin heavy chain variable region (VH) cDNA was amplifiedby PCR using an MHV7 primer (MHV7: 5′-ATGGRATGGAGCKGGRTCTTTMTCTT-3′ [SEQID NO: 1]) in combination with a IgG2b constant region primerMHCG1/2a/2b/3 mixture (MHCG1: 5′-CAGTGGATAGACAGATGGGGG-3′ [SEQ ID NO:2]; MHCG2a: 5′-CAGTGGATAGACCGATGGGGC-3 [SEQ ID NO: 3]; MHCG2b:5′-CAGTGGATAGACTGATGGGGG-3′ [SEQ ID NO: 4]; MHCG3:5′-CAAGGGATAGACAGATGGGGC-3′ [SEQ ID NO: 5]). The product of the reactionwas ligated into the pCR2.1®-TOPO® vector (Invitrogen) using the TOPO-TAcloning® kit and sequence. The variable domain of the heavy chain wasthen amplified by PCR from this vector and inserted as a Hind III andApa I fragment and ligated into the expression vector pG1D200 (see U.S.Pat. No. 7,060,808) or pG4D200 (id.) containing the HCMVi promoter, aleader sequence, and the gamma-1 constant region to generate the plasmidpG1D200306DVH (FIG. 10). The consensus sequence of 306D VH (shown below)showed that the constant region fragment was consistent with a gamma 2bisotype.

Similarly, the immunoglobulin kappa chain variable region (VK) wasamplified using the MKV 20 primer (5′-GTCTCTGATTCTAGGGCA-3′ [SEQ ID NO:6]) in combination with the kappa constant region primer MKC(5′-ACTGGATGGTGGGAAGATGG-3′ [SEQ ID NO: 7]). The product of thisreaction was ligated into the pCR2.1®-TOPO® vector using the TOPO-TAcloning® kit and sequence. The variable domain of the light chain wasthen amplified by PCR and then inserted as a Bam HI and Hind IIIfragment into the expression vector pKN100 (see U.S. Pat. No. 7,060,808)containing the HCMV promoter, a leader sequence, and the human kappaconstant domain, generating plasmid pKN100306DVK.

The heavy and light chain plasmids pG1D200306DVH plus pKN100306DVK weretransformed into DH4a bacteria and stocked in glycerol. Large-scaleplasmid DNA was prepared as described by the manufacturer (Qiagen,endotoxin-free MAXIPREP™ kit). DNA samples, purified using Qiagen'sQIAprep Spin Miniprep Kit or EndoFree Plasmid Mega/Maxi Kit, weresequenced using an ABI 3730x1 automated sequencer, which also translatesthe fluorescent signals into their corresponding nucleobase sequence.Primers were designed at the 5′ and 3′ ends so that the sequenceobtained would overlap. The length of the primers was 18-24 bases, andpreferably they contained 50% GC content and no predicted dimers orsecondary structure. The amino acid sequences for the mouse VH and VLdomains from Sphingomab™ are SEQ ID NOS: 8 and 9, respectively (Table2). The CDR residues (see Kabat, EA (1982), Pharmacol Rev, vol. 34:23-38) are underlined in Table 2, and are shown separately below inTable 3.

TABLE 2 V_(H) and V_(L) domains from the murine mAb, Sphingomab ™ mouseQAHLQQSDAELVKPGASVKISCKVSGFIFIDHTIHW SEQ ID VHMKQRPEQGLEWIGCISPRHDITKYNEMFRGKATLTA NO: 8 domainsDKSSTTAYIQVNSLTFEDSAVYFCARGGFYGSTIWf DFWGQGTTLTVS mouseETTVTQSPASLSMAIGEKVTIRCITTTDIDDDMNWF SEQ ID VLQQKPGEPPNLLISEGNILRPGVPSRFSSSGYGTDFL NO: 9 domainsFTIENMLSEDVADYYCLQSDNLPFTFGSGTKLEIK

TABLE 3 Mouse Sphingomab ™ CDR sequences of the mouse V_(H) and V_(L)domains CDR VL CDR ITTTDIDDDMN CDR1 (SEQ ID NO: 10) EGNILRP CDR2 (SEQ IDNO: 11) LQSDNLPFT CDR3 (SEQ ID NO: 12) VH CDR DHTIH CDR1 (SEQ ID NO: 13)CISPRHDITKYNEMFRG CDR2 (SEQ ID NO: 14) GGFYGSTIWFDF CDR3 (SEQ ID NO: 15)

The amino acid sequences of several chimeric antibody variable (VH andVL) domains are compared in Table 4. These variants were cloned intoexpression vectors behind germ line leader sequences. The germ lineleader sequences are underlined in Table 4 on the pATH200 (first 19amino acids) and pATH300 sequences (first 22 amino acids). The CDRs areshown in bold. Amino acids that follow the C-terminus of each of theheavy and light chain sequences in Table 4 are shown in italics. Theseare the first few amino acids of the constant domain and not part of thevariable domain.

It should be noted that while the pATH200 and pATH300 series numbersusually refer to a vector containing a particular variable domainvariant sequence, for convenience this nomenclature may be used hereinto refer to and distinguish the variant variable domains per se.

Sequences of the murine V_(H) and V_(L) domains were used to construct amolecular model to determine which framework residues should beincorporated into the humanized antibody.

TABLE 4 Amino acid sequences of the humanized VH (pATH200 series) and VL(pATH300 series) domains from the humanized anti-S1P antibody variants.Leaders are underlined, CDRs are in bold. VH Variants pATH200 SEQ ID NO:16mgstailalllavlqgvcsevqlvqsgaevkkpgeslkiscqsfgyifidhtihwvrqmpgqglewmgcisprhditkynpATH201.......................................................m........................pATH202.............................................f.........m..........i.............pATH203..................................................................i.............pATH204.............................................f..................................pATH205.............................................f.........m..........i.............pATH206....................a........................f.........m..........i.............pATH207.......................................................m............a...........path200 SEQ ID NO: 16emfrgqvtisadkssstaylqwsslkasdtamyifcarggfygstiwfdfwgqgtmvtvssastkgpspATH201....................................................................pATH202....................................................................pATH203....................................................................pATH204....................................................................pATH205......a.l...........................................................pATH206......a.l...........................................................pATH207.................................................................... VLVariants pATH300 (SEQ ID NO: 17)mdmrvpaqllgllllwlpgarcettltqspsflsasvgdrvtitcitttdidddmnwyqqepgkapklliyegnilrpgvpATH301......................................................................s.........pATH302.........................................................f......................pATH303.........................v............................................s.........pATH304.........................................................f............s.........pATH305.........................v...............................f............s.........pATH306.........................v...............................f............s.........pATH308.........................v...............................f............s.........pATH309......................................................................s.........pATH300 (SEQ ID NO: 17)psrifsgsgsgtdftltisklqpedfatyyclqsdnlpftfgqgtkleikrewip pATH301....................................................... pATH302....................................................... pATH303......................................................- pATH304....................................................... pATH305.....................................................-- pATH306.....s...............................................-- pATH308.....s..y.............................................. pATH309.....s..y..............................................

2. Expression and Binding Properties of the Chimeric Antibody

The heavy and light chain plasmids of both pG1D200306DVH pluspKN100306DVK were transformed into DH4a bacteria and stocked inglycerol. Large scale plasmid DNA was prepared as described by themanufacturer (Qiagen, endotoxin-free MAXIPREP™ kit Cat. No. 12362).

For antibody expression in a non-human mammalian system, plasmids weretransfected into the African green monkey kidney fibroblast cell lineCOS 7 by electroporation (0.7 ml at 10⁷ cells/ml) using 10 ug of eachplasmid. Transfected cells were plated in 8 ml of growth medium for 4days. The chimeric 306DH1×306DVK-2 antibody was expressed at 1.5 μg/mlin transiently co-transfected COS cell conditioned medium. The bindingof this antibody to S1P was measured using the S1P ELISA.

The expression level of the chimeric antibody was determined in aquantitative ELISA as follows. Microtiter plates (Nunc MaxiSorpimmunoplate, Invitrogen) were coated with 100 μl aliquots of 0.4 μg/mlgoat anti-human IgG antibody (Sigma, St. Louis, Mo.) diluted in PBS andincubate overnight at 4° C. The plates were then washed three times with200 μl/well of washing buffer (1× PBS, 0.1% TWEEN). Aliquots of 200 μLof each diluted serum sample or fusion supernatant were transferred tothe toxin-coated plates and incubated for 37° C. for 1 hr. Following 6washes with washing buffer, the goat anti-human kappa light chainperoxidase conjugate (Jackson Immuno Research) was added to each well ata 1:5000 dilution. The reaction was carried out for 1 hr at roomtemperature, plates were washed 6 times with the washing buffer, and 150μL of the K-BLUE substrate (Sigma) was added to each well, incubated inthe dark at room temperature for 10 min. The reaction was stopped byadding 50 μl of RED STOP solution (SkyBio Ltd.) and the absorption wasdetermined at 655 nm using a Microplater Reader 3550 (Bio-RadLaboratories Ltd.). Results from the antibody binding assays are shownin FIG. 11.

3 . 293F Expression

The heavy and light chain plasmids were transformed into Top 10 E. coli(One Shot Top 10 chemically competent E. coli cells (Invitrogen,C4040-10)) and stocked in glycerol. Large scale plasmid DNA was preparedas described by the manufacturer (Qiagen, endotoxin-free MAXIPREP™ kitCat No 12362).

For antibody expression in a human system, plasmids were transfectedinto the human embryonic kidney cell line 293F (Invitrogen) using 293fectin (Invitrogen) and using 293F-FreeStyle Media (Invitrogen) forculture. Light and heavy chain plasmids were both transfected at 0.5g/mL. Transfections were performed at a cell density of 10⁶ cells/mL.Supernatants were collected by centrifugation at 1100 rpm for 5 minutesat 25° C. 3 days after transfection. Expression levels were quantifiedby quantitative ELISA (see previous examples) and varied from ˜0.25-0.5g/mL for the chimeric antibody.

4. Antibody Purification

Monoclonal antibodies were purified from culture supernatants by passingculture supernatants over protein A/G columns (Pierce, Cat. No 53133) at0.5 mL/min. Mobile phases consisted of 1× Pierce IgG binding Buffer(Cat. No 21001) and 0.1 M glycine pH 2.7 (Pierce, Elution Buffer, Cat.No 21004). Antibody collections in 0.1 M glycine were diluted 10% (v/v)with 1 M Phosphate Buffer, pH 8.0, to neutralize the pH. IgG₁collections were pooled and dialyzed exhaustively against 1× PBS (PierceSlide-A-Lyzer Cassette, 3,500 MWCO, Cat. No 66382). Eluates wereconcentrated using Centricon YM-3(10,000 MWCO Amicon Cat. No 4203) bycentrifugation for 1 h at 2,500 rcf. The antibody concentration wasdetermined by quantitative ELISA as described above using a commercialmyeloma IgG₁ stock solution as a standard. Heavy chain isotypes of themAbs were determined by ELISA using Monoclonal Antibody Isotyping Kit(Sigma, ISO-2).

5. Comparative Binding of Antibody Variants to S1P

Table 5, below, shows a comparative analysis of mutants with thechimeric antibody. To generate these results, bound antibody wasdetected by a second antibody, specific for the mouse or human IgG,conjugated with HRP. The chromogenic reaction was measured and reportedas optical density (OD). The concentration of the panel of antibodieswas 0.1 ug/ml. No interaction of the second antibody with S1P-coatedmatrix alone was detected.

TABLE 5 Comparative binding to S1P on variants of the chimeric anti-S1Pantibody. Variable Domain Mutation Plasmids Binding Chimeric pATH50 +pATH10 1.5 HC CysAla pATH50 + pATH11 2 CysSer pATH50 + pATH12 0.6 CysArgpATH50 + pATH14 0.4 CysPhe pATH50 + pATH16 2 LC MetLeu pATH53 + pATH101.6

6. Determination of Binding Kinetics by Surface Plasmon Resonance (SPR)

All binding data were collected on a Biacore 2000 optical biosensor(Biacore AB, Uppsala Sweden). S1P was coupled to a maleimide CM5 sensorchip. First the CM5 chip was activated with an equal mixture of NHS/EDCfor seven minutes followed by a 7 minute blocking step withethyldiamine. Next sulfo-MBS (Pierce Co.) was passed over the surfacesat a concentration of 0.5 mM in HBS running buffer (10 mM HEPES, 150 mMNaCl, 0.005% p20, pH 7.4). S1P was diluted into the HBS running bufferto a concentration of 0.1 mM and injected for different lengths of timeproducing 2 different density S1P surfaces (305 and 470 RU). Next,binding data for the mAb was collected using a 3-fold dilution seriesstarting with 16.7 nM, 500 nM, 500 nM, 16.7 nM, and 16.7 nM for themouse, 201308, 201309, and 207308 antibodies respectively.

Each concentration was tested in duplicate. Surfaces were regeneratedwith 50 mM NaOH. All data were collected at 25° C. Responses data wereprocessed using a reference surface as well as blank injections. Thedata sets (responses from two surfaces and each variant tested twicewere fit to interaction models to obtain binding parameters. Data fromthe different mAb concentrations were globally fitted using a 1:1(mouse) or 1:2 (variants) interaction model to determine apparentbinding rate constants. The number in parentheses indicates the error inthe last digit.

Example 11 Chimeric mAb to S1P

As used herein, the term “chimeric” antibody (or “immunoglobulin”)refers to a molecule comprising a heavy and/or light chain which isidentical with or homologous to corresponding sequences in antibodiesderived from a particular species or belonging to a particular antibodyclass or subclass, while the remainder of the chain(s) is identical withor homologous to corresponding sequences in antibodies derived fromanother species or belonging to another antibody class or subclass, aswell as fragments of such antibodies, so long as they exhibit thedesired biological activity (Cabilly, et al., supra; Morrison et al.,Proc. Natl. Acad. Sci. U.S.A. 81:6851 (1984)).

A chimeric antibody to S1P was generated using the variable regions (Fv)containing the active S1P binding regions of the murine antibody from aparticular hybridoma (ATCC safety deposit storage number SD-5362) withthe constant regions of a human IgG1/kappa immunoglobulin. The constantregions contained the CL, CH1, CH2, hinge region, and CH3 domains of thehuman antibody. Without being limited to a particular method, chimericantibodies could also have been generated from heavy chain constantregions of human IgG1, IgG2, IgG3, IgG4, IgA, or IgM. As those in theart will appreciate, “humanized” antibodies can been generated bygrafting the complementarity determining regions (CDRs, e.g. CDR1-4) ofthe murine anti-S1P mAb with a human antibody framework regions (e.g.,FR1, FR2, FR3, and FR4) to appropriate human framework constant regions,such as, for example, the framework regions of an IgG1. FIG. 11 showsthe binding of the chimeric and full murine mAbs in a direct ELISAmeasurement using thiolated-S1P as lay down material.

For the direct ELISA experiments shown in FIG. 11, the chimeric antibodyto S1P had similar binding characteristics to the fully murinemonoclonal antibody. ELISAs were performed in 96-well high-binding ELISAplates (Costar) coated with 0.1 ug of chemically-synthesized, thiolatedS1P conjugated to BSA in binding buffer (33.6 mM Na₂CO₃, 100 mM NaHCO₃;pH 9.5). The thiolated S1P-BSA was incubated at 37° C. for 1 hr. or at4° C. overnight in the ELISA plate. Plates were then washed four timeswith PBS (137 mM NaCl, 2.68 mM KCl, 10.14 mM Na₂HPO₄, 1.76 mM KH₂PO₄; pH7.4) and blocked with PBST for 1 hr. at room temperature. For theprimary incubation step, 75 uL of the sample (containing the S1P to bemeasured), was incubated with 25 μL of 0.1 μg/mL anti-S1P monoclonalantibody diluted in PBST and added to a well of the ELISA plate. Eachsample was performed in triplicate wells. Following a 1 hr. incubationat room temperature, the ELISA plates were washed four times with PBSand incubated with 100 ul per well of 0.1 ug/mL HRP goat anti-mousesecondary (Jackson Immunoresearch) for 1 hr. at room temperature. Plateswere then washed four times with PBS and exposed to tetramethylbenzidine(Sigma) for 1-10 minutes. The detection reaction was stopped by theaddition of an equal volume of 1M H₂SO₄. Optical density of the sampleswas determined by measurement at 450 nm using an EL-X-800 ELISA platereader (Bio-Tech).

Again, the preferred method of measuring either antibody titer in theserum of an immunized animal or in cell-conditioned media (for example,supernatant) of an antibody-producing cell such as a hybridoma, involvescoating the ELISA plate with a target ligand (e.g., a thiolated analogof S1P, LPA, etc.) that has been covalently linked to a protein carriersuch as BSA.

Without being limited to particular method or example, chimericantibodies could be generated against other lipid targets such as LPA,PAF, ceramides, sulfatides, cerebrosides, cardiolipins,phosphotidylserines, phosphotidylinositols, phosphatidic acids,phosphotidylcholines, phosphatidylethanolamines, eicosinoids, and otherleukotrienes, etc. Further, many of these lipids could also beglycosylated and/or acetylated, if desired.

Example 12 Generation and Characterization of Humanized Anti-S1PMonoclonal Antibody LT1009 (Sonepcizumab)

The murine anti-S1P monoclonal antibody 306D (LT1002; Sphingomab™),which specifically binds S1P, has been shown to potently suppressangiogenesis and tumor growth in various animal models. As discussedbelow, LT1002 was humanized using sequence identity and homologysearches for human frameworks into which to graft the murine CDRs and acomputer-generated model to guide some framework backmutations. Twovariants, HuMAbHCLC₃ (LT1004) (with 3 backmutations in the light chain)and HuMAbHCLC₅ (LT1006) (with 5 backmutations in the light chain)exhibited binding affinity in the nanomolar range. Further engineeringwas performed in an effort to improve the biophysical and biologicalproperties of the humanized variants. The humanized variantsHuMAbHC_(CysAla)LC₃ (LT1007) and HuMAbHC_(CysAla)LC₅ (LT1009) in which afree-cysteine residue in HCDR2 was replaced with alanine exhibited abinding affinity in the picomolar range. All humanized variantsinhibited angiogenesis in the choroid neovascularization (CNV) model ofage-related macular degeneration (AMD), with HuMAbHC_(CysAla)LC₅(LT1009) exhibiting superior stability and in vivo efficacy compared tothe parent murine antibody. The variant huMAbHCcysalaLC₅ (LT1009) wasdesignated Sonepcizumab™.

a. Humanization Design for the Anti-S1P Antibody

The variable domains of murine mAb LT1002 (Sphingomab™) were humanizedvia CDR grafting (Winter U.S. Pat. No. 5,225,539). The CDR residues wereidentified based on sequence hypervariability as described by Kabat etal. 1991.

In this study, suitable acceptor structures were selected based on ahomology search of human antibodies in the IMGT and Kabat databasesusing a structural alignment program (SR v7.6). The initial step was toquery these human heavy variable (VH) and light variable (VL) sequencedatabases with LT1002 VH and VL protein sequences respectively, toidentify human frameworks (FR) with high sequence identity in the FR, atVernier (Foote, J. & Winter,G. Antibody framework residues affecting theconformation of the hypervariable loops. J Mol. Biol. 224, 487-499(1992)), Canonical (Morea, et al., Antibody modeling: implications forengineering and design, Methods 20, 267-279 (2000) and VH-VL interface(Chothia, C., Novotny, J., Bruccoleri, R., & Karplus, M. Domainassociation in immunoglobulin molecules. The packing of variabledomains. J Mol. Biol. 186, 651-663 (1985)) residues and with CDRs ofidentical canonical class and/or length. The identity of each member ofthis library to individual aligned residues of the mouse antibody wascalculated using the program. Those human sequences with FR sequencemost identical to the mouse FR were identified, producing an initialshortlist of human “acceptor” sequences. Those sequences with mostidentity to the mouse antibody, at Vernier, Canonical and VH-VLInterface (VCI) residues, were also calculated. Differences at thesepositions between human and mouse were classified into conservative andnon-conservative substitutions, so that the best framework choice wouldhave the lowest number of non-conservative VCI differences from LT1002.The CDR loops L3 and H1 of LT1002 could be classified into canonicalstructures. These L3 and H1 structures were used to select humanantibody FRs with identical canonical structures. For unclassified CDRs,an attempt was made to select human frameworks with CDR lengthsidentical to the mouse antibody. The rationale is that CDR loopstructures are dependent not only on the CDR loop sequence itself, butalso on the underlying framework residues (canonical residues).Therefore a human framework with matching canonical CDR structuresand/or CDR lengths is likely to hold the grafted mouse CDRs in the mostappropriate orientation to maintain antigen binding affinity. This wasachieved for all CDRs except CDR H3, by the choice of human frameworksequences. Additionally, frameworks with unusual cysteine or prolineresidues were excluded where possible. These calculations were performedseparately for the heavy and light chain sequences. Finally, individualsequence differences, throughout the framework region, in the bestmatching sequences were compared. Of the human antibodies that best fitthe above comparative calculations, the antibodies AY050707 and AJ002773were selected as the most appropriate human framework acceptors for thelight chain and the heavy chain respectively. The AY050707 framework wasdescribed by van den Brink, et al. (Blood, 15 Apr. 2002, Vol. 99, No. 8,pp 2828-2834) and its sequence is available via Genbank (accession no.AY050707; Homo sapiens clone WR3VL immunoglobulin light chain variableregion mRNA, partial cds.; submitted Nov. 13, 2001, last revision Apr.8, 2002).

Similarly, the AJ002773 antibody framework was described by Snow, et al.[Eur. J. Immunol. 28 (10), 3354-3361 (1998)], and its sequence isavailable via Genbank (accession no. AJ002772; Homo sapiens mRNA forvariable region 5 of immunoglobulin G4 heavy chain patient 2,2;submitted Nov. 6, 1998, last revision Oct. 16, 2006).

Both the AY050707 (light chain) and the AJ002773 (heavy chain) sequencesare also found in IMGT/LIGM, a comprehensive database of immunoglobulin(IG) and T cell receptor (TR) nucleotide sequences from human and othervertebrate species. This database was created in 1989 by Marie-PauleLefranc, LIGM, Montpellier, France, and has been available online sinceJuly 1995.

The second step was to generate a molecular model of the variableregions of LT1002 and to identify FR residues which might affect antigenbinding but were not included in the group of Vernier, Canonical andInterface residues. Many structural features of the graft donor andacceptor variable domains were examined in order to better understandhow various FR residues influence the conformation of the CDR loops andvice versa. Non-conserved FR residues in LT1002 that were likely toimpact the CDRs were identified from the Vernier and Canonicaldefinitions (see above) and thus several residues of the human FR wererestored to the original murine amino acids (backmutated).

b. Mutagenesis

Mutations within the variable domain sequences were created using theQuikChange Site-Directed Mutagenesis Kit (Stratagene, Catalog #200524).Individual reactions were carried out with 50 ng of double-stranded DNAtemplate, 2.5 U of PfuUltre HF DNA polymerase and its correspondingbuffer (Stratagene, Catalog #200524), 10 mM dNTP mix and 125 ng of eachof the mutagenic oligonucleotides resuspended in 5 mM Tris-HCl (pH 8.0),and 0.1 mM EDTA. The initial denaturation was carried out at 95° C. for30 seconds, followed by 16 cycles of amplification: 95° C. for 30seconds, 55° C. for 60 seconds and 68° C. for 8 min. Followingtemperature cycling, the final reaction was then digested with DpnIdigest at 37° C. for 1 hr to remove methylated parental DNA. Theresultant mutant was transformed into competent XL1-Blue E. coli andplated on LB-agar containing 50 μg/ml Ampicillin. The colonies were thenchecked by sequencing. Each of the mutants were then cultured in 1 litershake flasks and purified using the EndoFree Plasmid Purification Kitfrom Qiagen, catalog #12362.

c. Generation of the Humanized Antibody Variants

A mouse-human chimeric antibody (chMAb S1P) was constructed by cloningthe variable domains of LT1002 into a vector that contained the humanconstant regions of the kappa and heavy chains to allow expression ofthe full length antibody into mammalian cells. The generation of thehumanized heavy chain was the result of the graft of the Kabat CDRs 1, 2and 3 from LT1002 VH into the acceptor framework of AJ002773. Thenearest germ line gene to AJ002773 was VH5-51, whose leader sequence wasincorporated, as a leader sequence, into the humanized heavy chainvariant. The protein sequence of pATH200, the first humanized version ofLT1002 VH, with the VH5-51 leader sequence, is shown in Table 4. In thecase of the VH domain of LT1002, residues at position 2, 27, 37, 48, 67and 69 were Vernier residues or at the interface of the VH and VLdomains and likely to influence CDR orientation. Position 37 appeared tobe critical for the interface between the VH and VL domains. Theresidues at these positions in the human framework were backmutated withthe murine residue found at the corresponding position. The mutations,V37M, M481 and Y27F, were tested individually. One version (pATH205)contained all 3 mutations together with V67A plus I69L and anotherversion (pATH206) contained all 5 mutations plus V2A.

The generation of the humanized light chain was the result of the graftof the Kabat CDRs 1, 2 and 3 from LT1002 VL into the acceptor frameworkof AY050707. The nearest germ line gene to AY050707 was L11, whoseleader sequence was incorporated into the humanized light chainconstruct. The protein sequence of pATH300 (LT1002 light chain) is shownin Table 4. Germline leader sequences are indicated by underlining inTable 4. In the case of VL, four non-conserved Vernier positions 4, 36,49, 64 were selected for backmutation to murine residues as they areinvolved in supporting the structure of the CDR loops. Inspection of themolecular model of LT1002 suggested that Tyr 67 is close to the CDRsurface and oriented towards the antigen binding plane and couldinteract with S1P. Therefore the S67Y backmutation was also added tolater humanized versions. Two mutations were introduced separately togenerate two versions containing either Y49S or Y36F. Several versionswere created with the following combinations of mutations: (Y49S, F4V),(Y49S, Y36F), (Y49S, Y36F, F4V), (Y49S, G64S), (Y49S, Y36F, F4V, G64S),(Y49S, Y36F, F4V, G64S, S67Y), (Y49S, G64S, S67Y).

d. Selection of the Humanized Lead Candidates

The variable regions of the basic grafted versions (pATH200 and pATH300)and all the variants containing backmutations were cloned intoexpression vectors containing the human VH or VL constant regions. Allthe humanized variants were produced in mammalian cells under the sameconditions as the chimeric (chMAb) antibody and were tested for bindingto S1P by ELISA. The yield was approximately 10-20 mg/l for thehumanized variants and 0.3-0.5 mg/l for chMAb S1P. SDS-PAGE underreducing conditions revealed two bands at 25 kDa and 50 kDa with highpurity (>98%), consistent with the expected masses of the light andheavy chains. A single band was observed under non-reducing conditionswith the expected mass of ˜150k. chMAb was used as a standard in thehumanized antibody binding assays because it contained the same variableregions as the parent mouse antibody and bore the same constant regionsas the humanized antibodies and therefore could be detected using thesame ELISA protocol.

The initial humanized antibody, in which the six murine CDRs weregrafted into unmutated human frameworks, did not show any detectablebinding to S1P (FIG. 11). The kappa light chain containing the 4backmutations (Y49S, Y36F, F4V and G64S), in association with chimericheavy chain, exhibited suboptimal binding to S1P as measured by ELISA.The incorporation of an additional mutation at position Y67significantly improved the binding. Version pATH308 which containedbackmutations Y49S, Y36F, F4V, G64S and S67Y and version pATH309 whichcontained the backmutations Y49S, G64S and S67Y, in association withchimeric heavy chain, both generated antibodies which bound S1Psimilarly to the chimeric antibody as determined by ELISA. The 2mutations Y36F and F4V were not considered necessary backmutations fromthe viewpoint of S1P binding. The engineering of 3 to 5 backmutations inthe VL framework was required to restore activity.

The incorporation of the Vernier backmutation V37M into the humanframework of the heavy chain, in association with the chimeric lightchain, was sufficient to restore a binding behavior similar to thechimeric antibody (FIG. 11).

In summary, humanization of the LT1002 VH domain required only one aminoacid from the murine framework sequence whereas the murine VL frameworkdomain, three or five murine residues had to be retained to achievebinding equivalent to the murine parent LT1002.

e. Optimization of a Humanized Lead Candidate

The murine anti-S1P antibody contains a free cysteine residue in CDR2(Cys50) of the heavy chain that could potentially cause some instabilityof the antibody molecule. Using site directed mutagenesis, variants ofpATH201 were created with substitution of the cysteine residue withalanine (huMAbHC_(CysAla)LC₃) (pATH207), glycine (huMAbHC_(CysAla)LC₃),serine (huMAbHC_(CysSer)LC₃), and phenylalanine (huMAbHC_(CysPhe)LC₃).The cysteine mutant heavy chain was also tested with the humanized lightchain (pATH 308) containing 5 backmutations(huMAbHC_(CysAla)LC₅=LT1009). The variants were expressed in mammaliancells and then characterized in a panel of in vitro assays. Importantly,the expression rate of the humanized variants was significantly higherthan for chMAb S1P.

f. In-Depth Characterization of the Humanized Lead Candidate

i. Specificity. The humanized variants were tested for specificity in acompetitive ELISA assay (FIG. 1) against S1P and several otherbiolipids. This assay has the added benefit to allow for epitopemapping. The humanized antibody LT1009 demonstrated no cross-reactivityto sphingosine (SPH), the immediate metabolic precursor of S1P, or LPA(lysophosphatidic acid), an important extracellular signaling moleculethat is structurally and functionally similar to S1P. Moreover, rhuMAbS1P did not recognize other structurally similar lipids and metabolites,including ceramide (CER), ceramide-1-phosphate (C1P). However asexpected LT1009 did cross-react with sphingosyl phosphocholine (SPC), alipid in which the free phosphate group of S1P is tied up with a cholineresidue. Importantly, all the humanized variants exhibited a specificityprofile comparable to the mouse antibody.

ii. Binding affinity. Biacore measurements of IgG binding to a S1Pcoated chip showed that the variants LT1004 or LT1006 exhibited bindingaffinity in the low nanomolar range similar to chMAb S1P as shown inFIG. 11. The humanized variants LT1007 and LT1009 in which the cysteineresidue was replaced with alanine exhibited a binding affinity in thepicomolar range similar to the murine parent LT1002 (Sphingomab™).

iii. Stability. The humanized variants were tested for stability afterchallenge at high temperature. The approximate midpoints of the thermalunfolding transitions (T_(M)) were determined for every humanizedvariant by subjecting the supernatants to temperatures ranging from 60to 74° C. These temperatures were chosen based on the denaturationprofile observed for the murine antibody molecule afterthermochallenging between a broad range of temperatures between 50 and80° C. The binding properties of each variant were determined before andafter thermochallenge. The murine antibody exhibited a T_(M) of 65° C.The variant huMAbHC_(CysAla)LC₅ (LT1009) exhibited superior T_(M)compared to all other variants. Table 6 shows the lead humanizedcandidates and their characteristics.

TABLE 6 Lead humanized S1P mAb candidates and characteristics Mutationsin Mutations in the Heavy the Light Chain Chain In vitro Activity Frame-Frame- Binding Affinity Specificity mAb Description CDR work CDR work(K_(D1)) (ELISA) LT1002 Murine mAb N/A N/A N/A N/A 0.026 ± 0.000 nM HighSphingomab LT1004 HuHCLC₃ 0 1 0 3 1.060 ± 0.010 nM High pATH201HCpATH309LC LT1006 HuHCLC₅ 0 1 0 5 0.690 ± 0.010 nM High pATH201HCpATH308LC LT1007 HuHC_(CysAla)LC₃ 1 1 0 3 0.0414 ± 0.0004 nM  pATH207HCpATH309LC LT1009 HuHC_(CysAla)LC₅ 1 1 0 5 0.056 ± 0.001 nM HighpATH207HC pATH308LC The number of mutations in the heavy and lightchains are indicated. The description column gives the identity of theheavy and light chains.

iv. Sequences

As with naturally occurring antibodies, LT1009 includes threecomplementarity determining regions (each a “CDR”) in each of the twolight chain polypeptides and each of the two heavy chain polypeptidesthat comprise each antibody molecule. The amino acid sequences for eachof these six CDRs is provided immediately below (“VL” designates thevariable region of the immunoglobulin light chain, whereas “VH”designates the variable region of the immunoglobulin heavy chain):

CDR1 VL: ITTTDIDDDMN [SEQ ID NO: 10] CDR2 VL: EGNILRP [SEQ ID NO: 11]CDR3 VL: LQSDNLPFT [SEQ ID NO: 12] CDR1 VH: DHTIH [SEQ ID NO: 13 CDR3VH: GGFYGSTIWFDF [SEQ ID NO: 15] CDR2 VH: AISPRHDITKYNEMFRG [SEQ ID NO:18]

Example 13 Humanized S1P mAb Production and Purification

This example describes the production of a recombinant humanizedmonoclonal antibody (LT1009; Sonepcizumab™) that binds with highaffinity to the bioactive lipid sphingosine-1-phosphate (S1P). LT1009 isa full-length IgG1/kappa isotype antibody composed of two identicallight chains and two identical heavy chains with a total molecularweight of approximately 150 kDa. The heavy chain contains an N-linkedglycosylation site. The nature of the oligosaccharide structure has notyet been determined but is anticipated to be a complex biantennarystructure with a core fucose. The nature of the glycoform that will bepredominant is not known at this stage. Some C-terminal heterogeneity isexpected because of the presence of lysine residues in the constantdomain of the heavy chain. The two heavy chains are covalently coupledto each other through two inter-chain disulfide bonds, which isconsistent with the structure of a human IgG1.

LT1009 was originally derived from a murine monoclonal antibody (LT1002;Sphingomab™) that was produced using hybridomas generated from miceimmunized with S1P. The humanization of the murine antibody involved theinsertion of the six murine CDRs in place of those of a human antibodyframework selected for its structure similarity to the murine parentantibody. A series of substitutions were made in the framework toengineer the humanized antibody. These substitutions are called backmutations and replace human with murine residues that are play asignificant role in the interaction of the antibody with the antigen.The final humanized version contains one murine back mutation in thehuman framework of variable domain of the heavy chain and five murineback mutations in the human framework of the variable domain of thelight chain. In addition, one residue present in the CDR2 of the heavychain was substituted to an alanine residue. This substitution was shownto increase stability and potency of the antibody molecule.

The humanized variable domains (both heavy and light chain) were clonedinto the Lonza's GS gene expression system to generate the plasmidpATH1009. The Lonza GS expression system consists of an expressionvector carrying the constant domains of the antibody genes and theselectable marker glutamine synthetase (GS). GS is the enzymeresponsible for the biosynthesis of glutamine from glutamate andammonia. The vector carrying both the antibody genes and the selectablemarker is transfected into a proprietary Chinese hamster ovary host cellline (CHOK1SV) adapted for growth in serum-free medium and providessufficient glutamine for the cell to survive without exogenousglutamine. In addition, the specific GS inhibitor, methioninesulphoximine (MSX), is supplemented in the medium to inhibit endogenousGS activity such that only the cell lines with GS activity provided bythe vector can survive. The resulting CHO cell line transfected withpATH1009 is named LH1.

It should be noted that the natural germ line gene leader sequencesdescribed in the above examples are replaced by leader sequences in theGS expression vector backbone used to produce the plasmid pATH1009. Thelatter leader sequences can be seen as 19 amino acids beginning“mewswv,” at the N-terminus of the LT1009 heavy chain (SEQ ID NO: 19 and24), and the LC leader is 20 amino acids beginning “msvpt” (as shown atthe N-terminus of SEQ ID NO: 20 and 26).

The transfected CHO LH1 cells were selected for their ability to grow inglutamine-free medium in the presence of MSX and isolates (clones) wereselected for high level of secretion of active LT1009. LH1 275 is thename given to the lead clone of the LH1 CHO cell line containing thepATH1009 vector selected for the creation of a Master Cell Bank (MCB)for production of all lots of LT1009 antibody product. Material fortoxicology studies and clinical development were then produced for toxand clinical development.

ATCC deposits: E. coli StB12 containing the pATH1009 plasmid has beendeposited with the American Type Culture Collection (deposit numberPTA-8421; received by the ATCC on 10 May 2007). Upon issuance of thispatent this cell line will be available CHO cell line LH1 275, whichcontains the pATH1009 vector has also been deposited with the AmericanType Culture Collection (deposit number PTA-8422; received by the ATCCon 10 May 2007). The ATCC is located at 10801 University Blvd.,Manassas, Va. 20110-2209.

Sequences:

The nucleotide and amino acid sequences for the heavy and light chainpolypeptides of LT1009 are listed immediately below. Leader sequences(from Lonza GS expression vector) are underlined; CDRs are in bold.

LT1009 HC amino acid sequence of the variable domain [SEQ ID NO: 19]:

1 mewswvflff lsvttgvhse vqlvqsgaev kkpgeslkis cqsfgyifid 51 htihwmrqmpgqglewmgai sprhditkyn emfrgqvtis adkssstayl 101 qwsslkasdt amyfcarggfygstiwfdfw gqgtmvtvssLT1009 LC amino acid sequence of the variable domain [SEQ ID NO: 20]:

1 msvptqvlgl lllwltdarc ettvtqspsf lsasvgdrvt itcitttdid 51 ddmnwfqqepgkapkllise gnilrpgvps rfsssgygtd ftltisklqp 101 edfatyyclq sdnlpftfgqgtkleikCorresponding nucleotide sequences encoding the heavy and light chainvariable domains are listed immediately below. Leader sequences (fromLonza GS expression vector) are underlined; sequences preceding theleader are HindIII cut site (aagctt) and Kozak consensus sequence(gccgccacc), which plays a major role in the initiation of translationprocess; CDRs are in bold:LT1009 HC nucleotide sequence of the variable domain [SEQ ID NO: 21]

1 aagcttgccg ccaccatgga atggagctgg gtgttcctgt tctttctgtc 51cgtgaccaca ggcgtgcatt ctgaggtgca gctggtgcag tctggagcag 101 aggtgaaaaagcccggggag tctctgaaga tctcctgtca gagttttgga 151 tacatcttta tcgaccatactattcactgg atgcgccaga tgcccgggca 201 aggcctggag tggatggggg ctatttctcccagacatgat attactaaat 251 acaatgagat gttcaggggc caggtcacca tctcagccgacaagtccagc 301 agcaccgcct acttgcagtg gagcagcctg aaggcctcgg acaccgccat351 gtatttctgt gcgagagggg ggttctacgg tagtactatc tggtttgact 401tttggggcca agggacaatg gtcaccgtct cttcaLT1009 LC nucleotide sequence of the variable domain [SEQ ID NO. 22]

1 aagcttgccg ccaccatgtc tgtgcctacc caggtgctgg gactgctgct 51gctgtggctg acagacgccc gctgtgaaac gacagtgacg cagtctccat 101 ccttcctgtctgcatctgta ggagacagag tcaccatcac ttgcataacc 151 accactgata ttgatgatgatatgaactgg ttccagcagg aaccagggaa 201 agcccctaag ctcctgatct ccgaaggcaatattcttcgt cctggggtcc 251 catcaagatt cagcagcagt ggatatggca cagatttcactctcaccatc 301 agcaaattgc agcctgaaga ttttgcaact tattactgtt tgcagagtga351 taacttacca ttcactttcg gccaagggac caagctggag atcaaaLT1009 full length HC nucleotide (cDNA) sequence [SEQ ID NO: 23] withCDRs in bold and leader region underlined; hinge region is in italics.Sequences preceding the leader are HindIII cut site (aagctt)_ and Kozaksequence (gccgccacc):

aagcttgccgccaccatggaatggagctgggtgttcctgttctttctgtccgtgaccacaggcgtgcattctgaggtgcagctggtgcagtctggagcagaggtgaaaaagcccggggagtctctgaagatctcctgtcagagttttggatacatctttatcgaccatactattcactggatgcgccagatgcccgggcaaggcctggagtggatgggggctatttctcccagacatgatattactaaatacaatgagatgttcaggggccaggtcaccatctcagccgacaagtccagcagcaccgcctacttgcagtggagcagcctgaaggcctcggacaccgccatgtatttctgtgcgagaggggggttctacggtagtactatctggtttgacttttggggccaagggacaatggtcaccgtctcttcagcctccaccaagggcccatcggtcttccccctggcaccctcctccaagagcacctctgggggcacagcggccctgggctgcctggtcaaggactacttccccgaaccggtgacggtgtcgtggaactcaggcgccctgaccagcggcgtgcacaccttcccggctgtcctacagtcctcaggactctactccctcagcagcgtggtgaccgtgccctccagcagcttgggcacccagacctacatctgcaacgtgaatcacaagcccagcaacaccaaggtggacaagagagttgagcccaaatcttgtgacaaaactcacacatgcccaccgtgcccagcacctgaactcctggggggaccgtcagtcttcctcttccccccaaaacccaaggacaccctcatgatctcccggacccctgaggtcacatgcgtggtggtggacgtgagccacgaagaccctgaggtcaagttcaactggtacgtggacggcgtggaggtgcataatgccaagacaaagccgcgggaggagcagtacaacagcacgtaccgtgtggtcagcgtcctcaccgtcctgcaccaggactggctgaatggcaaggagtacaagtgcaaggtctccaacaaagccctcccagcccccatcgagaaaaccatctccaaagccaaagggcagccccgagaaccacaggtgtacaccctgcccccatcccgggaggagatgaccaagaaccaggtcagcctgacctgcctggtcaaaggcttctatcccagcgacatcgccgtggagtgggagagcaatgggcagccggagaacaactacaagaccacgcctcccgtgctggactccgacggctccttcttcctctatagcaagctcaccgtggacaagagcaggtggcagcaggggaacgtcttctcatgctccgtgatgcatgaggctctgcacaaccactacacgcagaagagcctctccctgtctccgggtaaatagLT1009 HC amino acid sequence, with leader (underlined) and minus thehinge region. CDRs are shown in bold. [SEQ ID NO: 24]:

1 mewswvflff lsvttgvhse vqlvqsgaev kkpgeslkis cqsfgyifid 51 htihwmrqmpgqglewmgai sprhditkyn emfrgqvtis adkssstayl 101 qwsslkasdt amyfcarggfygstiwfdfw gqgtmvtvss astkgpsvfp 151 lapsskstsg gtaalgclvk dyfpepvtvswnsgaltsgv htfpavlqss 201 glyslssvvt vpssslgtqt yicnvnhkps ntkvdkrvapellggpsvfl 251 fppkpkdtlm isrtpevtcv vvdvshedpe vkfnwyvdgv evhnaktkpr301 eeqynstyrv vsvltvlhqd wlngkeykck vsnkalpapi ektiskakgq 351prepqvytlp psreemtknq vsltclvkgf ypsdiavewe sngqpennyk 401 ttppvldsdgsfflyskltv dksrwqqgnv fscsvmheal hnhytqksls 451 lspgkLT1009 LC full length nucleotide sequence [SEQ ID NO: 25] with leaderunderlined and CDRs in bold; sequences preceding the leader are HindIIIcut site (aagctt) and Kozak sequence (gccgccacc):

1 aagcttgccg ccaccatgtc tgtgcctacc caggtgctgg gactgctgct 51gctgtggctg acagacgccc gctgtgaaac gacagtgacg cagtctccat 101 ccttcctgtctgcatctgta ggagacagag tcaccatcac ttgcataacc 151 accactgata ttgatgatgatatgaactgg ttccagcagg aaccagggaa 201 agcccctaag ctcctgatct ccgaaggcaatattcttcgt cctggggtcc 251 catcaagatt cagcagcagt ggatatggca cagatttcactctcaccatc 301 agcaaattgc agcctgaaga ttttgcaact tattactgtt tgcagagtga351 taacttacca ttcactttcg gccaagggac caagctggag atcaaacgta 401cggtggctgc accatctgtc ttcatcttcc cgccatctga tgagcagttg 451 aaatctggaactgcctctgt tgtgtgcctg ctgaataact tctatcccag 501 agaggccaaa gtacagtggaaggtggataa cgccctccaa tcgggtaact 551 cccaggagag tgtcacagag caggacagcaaggacagcac ctacagcctc 601 agcagcaccc tgacgctgag caaagcagac tacgagaaacacaaagtcta 651 cgcctgcgaa gtcacccatc agggcctgag ctcgcccgtc acaaagagct701 tcaacagggg agagtgttagLT1009 LC amino acid sequence with leader underlined and CDRs in bold[SEQ ID NO: 26]:

1 msvptqvlgl lllwltdarc ettvtqspsf lsasvgdrvt itcitttdid 51 ddmnwfqqepgkapkllise gnilrpgvps rfsssgygtd ftltisklqp 101 edfatyyclq sdnlpftfgqgtkleikrtv aapsvfifpp sdeqlksgta 151 svvcllnnfy preakvqwkv dnalqsgnsqesvteqdskd styslsstlt 201 lskadyekhk vyacevthqg lsspvtksfn rgecSequences of the LT1009 heavy and light chains without leader sequences(and without preceding nuclease cut sites and Kozak sequences) are asfollows. CDRs are shown in bold.LT1009 HC amino acid sequence of the variable domain [SEQ ID NO: 27]:

evqlvqsgaevkkpgeslkiscqsfgyifidhtihwmrqmpgqglewmgaisprhditkynemfrgqvtisadkssstaylqwsslkasdtamyfcargg fygstiwfdfwgqgtmvtvssCorresponding LT1009 HC nucleotide sequence encoding the variable domain[SEQ ID NO: 28]:

gaggtgcagctggtgcagtctggagcagaggtgaaaaagcccggggagtctctgaagatctcctgtcagagttttggatacatctttatcgaccatactattcactggatgcgccagatgcccgggcaaggcctggagtggatgggggctatttctcccagacatgatattactaaatacaatgagatgttcaggggccaggtcaccatctcagccgacaagtccagcagcaccgcctacttgcagtggagcagcctgaaggcctcggacaccgccatgtatttctgtgcgagaggggggttctacggtagtactatctggtttgacttttggggccaagggacaatggt caccgtctcttcaLT1009 LC amino acid sequence of the variable domain [SEQ ID NO: 29]:

ettvtqspsflsasvgdrvtitcitttdidddmnwfqqepgkapkllisegnilrpgvpsrfsssgygtdftltisklqpedfatyyclqsdnlpftfgq gtkleikCorresponding LT1009 LC nucleotide sequence encoding the variable domain[SEQ ID NO. 30]

gaaacgacagtgacgcagtctccatccttcctgtctgcatctgtaggagacagagtcaccatcacttgcataaccaccactgatattgatgatgatatgaactggttccagcaggaaccagggaaagcccctaagctcctgatctccgaaggcaatattcttcgtcctggggtcccatcaagattcagcagcagtggatatggcacagatttcactctcaccatcagcaaattgcagcctgaagattttgcaacttattactgtttgcagagtgataacttaccattcactttcggccaa gggaccaagctggagatcaaaThe amino acid sequences of the full length LT1009 heavy and lightchains without leaders are as follows (CDRs are in bold):LT1009 full length heavy chain amino acid sequence without leader (andwithout preceding nuclease cleavage site and Kozak sequence) andincluding hinge (underlined). (SEQ ID NO: 31)

evqlvqsgaevkkpgeslkiscqsfgyifidhtihwmrqmpgqglewmgaisprhditkynemfrgqvtisadkssstaylqwsslkasdtamyfcarggfygstiwfdfwgqgtmvtvssastkgpsvfplapsskstsggtaalgclvkdyfpepvtvswnsgaltsgvhtfpavlqssglyslssvvtvpssslgtqtyicnvnhkpsntkvdkrvepkscdkthtcppcpapellggpsvflfppkpkdtlmisrtpevtcvvvdvshedpevkfnwyvdgvevhnaktkpreeqynstyrvvsvltvlhqdwlngkeykckvsnkalpapiektiskakgqprepqvytlppsreemtknqvsltclvkgfypsdiavewesngqpennykttppvldsdgsfflyskltvdksrwqqgnvfscsvmhealhnhytqkslslsp gkLT1009 full length light chain amino acid sequence without leader. [SEQID NO 32]:

ettvtqspsflsasvgdrvtitcitttdidddmnwfqqepgkapkllisegnilrpgvpsrfsssgygtdftltisklqpedfatyyclqsdnlpftfgqgtkleikrtvaapsvfifppsdeqlksgtasvvcllnnfypreakvqwkvdnalqsgnsqesvteqdskdstyslsstltlskadyekhkvyacevth qglsspvtksfnrgecThe corresponding nucleotide sequences (without leaders or precedingnuclease or Kozak sites) are below. It will be understood that due tothe degeneracy of the genetic code, alternative nucleotide sequencesalso may encode virtually any given amino acid sequence.LT1009 full length heavy chain nucleotide (cDNA) sequence [SEQ ID NO:33]:

gaggtgcagctggtgcagtctggagcagaggtgaaaaagcccggggagtctctgaagatctcctgtcagagttttggatacatctttatcgaccatactattcactggatgcgccagatgcccgggcaaggcctggagtggatgggggctatttctcccagacatgatattactaaatacaatgagatgttcaggggccaggtcaccatctcagccgacaagtccagcagcaccgcctacttgcagtggagcagcctgaaggcctcggacaccgccatgtatttctgtgcgagaggggggttctacggtagtactatctggtttgacttttggggccaagggacaatggtcaccgtctcttcagcctccaccaagggcccatcggtcttccccctggcaccctcctccaagagcacctctgggggcacagcggccctgggctgcctggtcaaggactacttccccgaaccggtgacggtgtcgtggaactcaggcgccctgaccagcggcgtgcacaccttcccggctgtcctacagtcctcaggactctactccctcagcagcgtggtgaccgtgccctccagcagcttgggcacccagacctacatctgcaacgtgaatcacaagcccagcaacaccaaggtggacaagagagttgagcccaaatcttgtgacaaaactcacacatgcccaccgtgcccagcacctgaactcctggggggaccgtcagtcttcctcttccccccaaaacccaaggacaccctcatgatctcccggacccctgaggtcacatgcgtggtggtggacgtgagccacgaagaccctgaggtcaagttcaactggtacgtggacggcgtggaggtgcataatgccaagacaaagccgcgggaggagcagtacaacagcacgtaccgtgtggtcagcgtcctcaccgtcctgcaccaggactggctgaatggcaaggagtacaagtgcaaggtctccaacaaagccctcccagcccccatcgagaaaaccatctccaaagccaaagggcagccccgagaaccacaggtgtacaccctgcccccatcccgggaggagatgaccaagaaccaggtcagcctgacctgcctggtcaaaggcttctatcccagcgacatcgccgtggagtgggagagcaatgggcagccggagaacaactacaagaccacgcctcccgtgctggactccgacggctccttcttcctctatagcaagctcaccgtggacaagagcaggtggcagcaggggaacgtcttctcatgctccgtgatgcatgaggctctgcacaaccactacacgcagaagagcctctccctgtctccgggt aaatagLT1009 full length light chain nucleotide sequence [SEQ ID NO 34]:

gaaacgacagtgacgcagtctccatccttcctgtctgcatctgtaggagacagagtcaccatcacttgcataaccaccactgatattgatgatgatatgaactggttccagcaggaaccagggaaagcccctaagctcctgatctccgaaggcaatattcttcgtcctggggtcccatcaagattcagcagcagtggatatggcacagatttcactctcaccatcagcaaattgcagcctgaagattttgcaacttattactgtttgcagagtgataacttaccattcactttcggccaagggaccaagctggagatcaaacgtacggtggctgcaccatctgtcttcatcttcccgccatctgatgagcagttgaaatctggaactgcctctgttgtgtgcctgctgaataacttctatcccagagaggccaaagtacagtggaaggtggataacgccctccaatcgggtaactcccaggagagtgtcacagagcaggacagcaaggacagcacctacagcctcagcagcaccctgacgctgagcaaagcagactacgagaaacacaaagtctacgcctgcgaagtcacccatcagggcctgagctcgcccgtcacaaagagcttcaacaggggagagtgttag

The C-Terminal Lysine on the LT1009 Heavy Chain may not Always bePresent on the Mature Heavy Chain Protein.

While the nucleotide and amino acid sequences for LT1009 heavy chainreveal a lysine as the last (most C-terminal) amino acid residue of theprotein, LT1009 when expressed, for example, in CHO cell clone LH1 275,does not contain the C-terminal lysine. This is shown by peptide mappingand, while not wishing to be bound by theory, is believed to result fromposttranslational modification of the protein in mammalian systems.Again not wishing to be bound by theory, it is believed that in otherexpression systems, particularly nonmammalian systems, the C-terminallysine is present on the mature LT1009 heavy chain.

The LT1009 heavy chain amino acid sequence as expressed in CHO cells(i.e., without leaders and without the C-terminal lysine) is shown below(CDRs are in bold, hinge in italics) [SEQ ID NO 35]:

evqlvqsgaevkkpgeslkiscqsfgyifidhtihwmrqmpgqglewmgaisprhditkynemfrgqvtisadkssstaylqwsslkasdtamyfcarggfygstiwfdfwgqgtmvtvssastkgpsvfplapsskstsggtaalgclvkdyfpepvtvswnsgaltsgvhtfpavlqssglyslssvvtvpssslgtqtyicnvnhkpsntkvdkrvepkscdkthtcppcpapellggpsvflfppkpkdtlmisrtpevtcvvvdvshedpevkfnwyvdgvevhnaktkpreeqynstyrvvsvltvlhqdwlngkeykckvsnkalpapiektiskakgqprepqvytlppsreemtknqvsltclvkgfypsdiavewesngqpennykttppvldsdgsfflyskltvdksrwqqgnvfscsvmhealhnhytqkslsl spgAn example of a nucleotide sequence that could encode this amino acidsequence is shown below as SEQ ID NO: 36. It will be understood that,due to the degeneracy of the genetic code, multiple nucleotide sequencesmay encode the same amino acid sequence, and for this reason, these andother nucleotide sequences shown herein as encoding amino acid sequencesare recognized to be for purposes of exemplification. CDRs are shown inbold and the hinge region is in italics:

gaggtgcagctggtgcagtctggagcagaggtgaaaaagcccggggagtctctgaagatctcctgtcagagttttggatacatctttatcgaccatactattcactggatgcgccagatgcccgggcaaggcctggagtggatgggggctatttctcccagacatgatattactaaatacaatgagatgttcaggggccaggtcaccatctcagccgacaagtccagcagcaccgcctacttgcagtggagcagcctgaaggcctcggacaccgccatgtatttctgtgcgagaggggggttctacggtagtactatctggtttgacttttggggccaagggacaatggtcaccgtctcttcagcctccaccaagggcccatcggtcttccccctggcaccctcctccaagagcacctctgggggcacagcggccctgggctgcctggtcaaggactacttccccgaaccggtgacggtgtcgtggaactcaggcgccctgaccagcggcgtgcacaccttcccggctgtcctacagtcctcaggactctactccctcagcagcgtggtgaccgtgccctccagcagcttgggcacccagacctacatctgcaacgtgaatcacaagcccagcaacaccaaggtggacaagagagttggtgagaggccagcacagggagggagggtgtctgctggaagccaggctcagcgctcctgcctggacgcatcccggctatgcagtcccagtccagggcagcaaggcaggccccgtctgcctcttcacccggaggcctctgcccgccccactcatgctcagggagagggtcttctggctttttccccaggctctgggcaggcacaggctaggtgcccctaacccaggccctgcacacaaaggggcaggtgctgggctcagacctgccaagagccatatccgggaggaccctgcccctgacctaagcccaccccaaaggccaaactctccactccctcagctcggacaccttctctcctcccagattccagtaactcccaatcttctctctgcagagcccaaatcttgtgacaaaactcacacatgcccaccgtgcccaggtaagccagcccaggcctcgccctccagctcaaggcgggacaggtgccctagagtagcctgcatccagggacaggccccagccgggtgctgacacgtccacctccatctcttcctcagcacctgaactcctggggggaccgtcagtcttcctcttccccccaaaacccaaggacaccctcatgatctcccggacccctgaggtcacatgcgtggtggtggacgtgagccacgaagaccctgaggtcaagttcaactggtacgtggacggcgtggaggtgcataatgccaagacaaagccgcgggaggagcagtacaacagcacgtaccgtgtggtcagcgtcctcaccgtcctgcaccaggactggctgaatggcaaggagtacaagtgcaaggtctccaacaaagccctcccagcccccatcgagaaaaccatctccaaagccaaaggtgggacccgtggggtgcgagggccacatggacagaggccggctcggcccaccctctgccctgagagtgaccgctgtaccaacctctgtccctacagggcagccccgagaaccacaggtgtacaccctgcccccatcccgggaggagatgaccaagaaccaggtcagcctgacctgcctggtcaaaggcttctatcccagcgacatcgccgtggagtgggagagcaatgggcagccggagaacaactacaagaccacgcctcccgtgctggactccgacggctccttcttcctctatagcaagctcaccgtggacaagagcaggtggcagcaggggaacgtcttctcatgctccgtgatgcatgaggctctgcacaaccactacacgcagaagagcctctccctgtct ccgggttag

Peptide Mapping of LT1009

Peptide mapping of LT1009 (four different lots, all expressed in CHOcell line LH1 275) was able to confirm >99% of the protein sequence. Theonly peptides not observed were single amino acids. Evidence of adeglycosylation reaction was present in fragment T23 of the heavy chain,wherein asparagine (N) was converted to aspartic acid (D) upondeglycosylation. This indicates prior glycosylation at this site, whichcorresponds to amino acid 301 (N) of the heavy chain amino acid sequence(as shown in, for example, SEQ ID NO: 31). It was also shown by peptidemapping that the C-terminal lysine was not present in the LT1009 heavychain as expressed in CHO cell line LH1 275.

Example 14 Manufacturing of Humanized mAb

Typically, the production process involves three stages: seed train,inoculum train, and the production culture. All stages use serum-freereagents and low protein cell culture growth medium. To initiate a seedtrain, cells from the working cell bank are used; cells are subculturedevery three to four days and after a prescribed period in the seed trainculture, the inoculation train is initiated. The non-selective medium(MTX-free medium) is preferably used to expand the cell for introductioninto the production stage. The cells are expanded by serialsub-cultivation into vessels of increasing volume. At a certain numberof days in the inoculum train, the production stage is initiated. Theproduction culture is performed in a bioreactor of volume of 200L, 400L,2000L, or 20000L. An example of a bioreactor is described below.

Example of bioreactor: Scale-up from the 2 L bioreactors will proceedfirst to a Applikon 15 L stirred tank, then sequentially to a 50 Lbioreactor, a 200 L bioreactor and finally a 2000 L bioreactor (allbuilt to same scale). The characteristics of these tanks are as follows:

Manufacturer: ABEC, Inc.

Fabricated to ASME, Section VIII Pressure Vessel Code. Contact surfacesare 316LSS.

Bottom offset drive, ABEC design

Lowshear impellor 316LSS, polished to 15-20 microinch and passivated.Diameter ˜½ of vessel diameter.

Controls: Allen Bradley Control Logic PLC, with Versa view operatorinterface.

Agitation: Allen Bradley sensor, A-B PLC control of output for VFI forRPM control

Temperature: Dual control 100 ohm platinum RTD sensor, A-B PLC controlheat, cold and steam valves w/recirculation pump. Automaticsterilization cycle with bioreactor empty.

pH: Ingold sensor, gel filled, pressurizable, A-B PLC control of CO2 tosparge.

Dissolved oxygen: Ingold polarographic electrode sensor, A-B PLC controlof O2 sparge.

Air and gas flow: Sensors are Four Brooks Thermal Mass Flowmeters forair, O2, N2 and CO2 sparging, a Brooks thermal mass is also supplied forair overlay, A-B PLC control of gas flows for pH auto, DO auto or manualcontrol of all gas flow through A-B PLC.

Vessel Pressure: Sensor is a Rosemount sanitary diaphragm typetransducer, control is A-B PLC control of transducer with back pressurecontrol valve.

Programmable Logic Controller (PLC): Allen Bradley Control Logix Systemfor sequential loop control of processes as indicated. Software: PLCprogramming utilizes Rockwell Software (Allen Bradley) RS Logix 5000.

Human Machine Interface (HMI): Local operator interface is on an AllenBradley HMI Verso View Industrial computer with integrated FPD/touchscreen entry communicating to the PLC via Ethernet. Software is RockwellSoftware RS View 32.

Example of Production Process.

Stirred stainless bioreactor with control of temperature, dissolvedoxygen and pH.

Seeding density is determined for optimal yield.

Serum-free medium is typically utilized.

Typically a fed-batch process.

Typically with a temperature shift.

Duration of culture in the bioreactor expected to be 8 to 14 days.

Viability at time of harvest to be defined.

Harvest will be clarified by filtration.

Harvest will be stored at 2-8° C. following clarification and prior topurification.

Example 15 Large-Scale Purification of Humanized mAb

The drug substance purification process typically consists of foursteps: protein A chromatography, anion exchange chromatography (Qsepharose), cation exchange chromatography (CM sepharose), andultrafiltration/diafiltration (UF/DF). The affinity column is thegenerally the first step after harvest and clarification. This columntypically utilizes an immobilized protein A resin. This affinity steppurifies the antibody with respect to host cell proteins and DNA. Inorder to inactivate potential viruses, the eluate is typically subjectedto a virus inactivation process followed by an anion exchangechromatographic step to reduce host cell proteins, DNA, protein A, andpotential viruses. Next, a cation exchange chromatographic step istypically used to further reduce the residual amounts of host cellproteins and antibody aggregates. Finally, the pool is then diafilteredand further concentrated.

Representative Purification Process:

Harvest may be concentrated and buffer-exchanged prior to Protein Acolumn. The next step in the process is Protein A column affinitychromatography. The bound antibody is eluted with a low pH buffer. TheProtein A eluate is held for a time in order to inactivate viruses.

The next step in the process can be an ion-exchange chromatography on aQ(+) column under conditions in which the antibody product flows throughand contaminants, such as DNA and host cell proteins bind to the columnresin.

The next step in the process can be a second ion-exchange chromatographyon an S(−) column under conditions in which contaminants flow throughthe column. A hydrophobic interaction column step may be used in placeof the S(−) column step. The next step in the process is likely to be ananofiltration virus removal step, using a DV20 or Planova filter. Theproduct flows through the filter. The final steps in the process arediafiltration into the final drug substance formulation buffer andultrafiltration to achieve the target protein concentration.

Example 16 Biological Activity of Humanized Variants of a MurineAnti-S1P Antibody

In vitro Cell Assays

The humanized antibodies were tested for their ability to alter tumorcell survival in presence of chemotherapeutic agents as shown in FIG.12. SKOV3 tumor cells were exposed to Taxol, a chemotherapeutic agentthat induces tumor cell death by activation of the apoptoticexecutioner, caspase-3. S1P was able to decrease Taxol-induced caspase-3activation and/or cell death compared to the control non-treated cells.Apoptosis assays were performed as recommended by the manufacturer(Promega, Cat. No G7792). Briefly, A549 cells (2500 cells per well) wereseeded into 96-well plates and allowed to grow to 80% confluence priorto treatment. The cells were then treated with and without 0.1-1 μMPaclitaxel (Sigma, Cat. No T 7409), 0.1-1 μM S1P and 1 μg/mL of theanti-S1P mAb, in McCoy's media for 48 hrs. After 48 hrs, the caspaseassay buffer was added to the cells. Caspase-3 activity in thesupernatant was measured by Apo-One Homogeneous Caspase-3/7 Assay kit(Promega, Cat. No G7792) according to the manufacturer's protocol.Caspase-3/7 activity is expressed as the fold increase in fluorescencesignal with respect to vehicle treated cells.

Caspase-3 activation was increased by the addition of anti-S1P mAb inpresence of S1P, suggesting that the protective anti-apoptotic effect ofS1P was eliminated by selective absorption of S1P by the antibody. Bothhumanized antibody variants, huMAbHCLC₃ (LT1004) and huMAbHCLC₅(LT1006), exhibited superior activity compared to LT1002. In parallel,all the variants were tested for their effects on S1P-induced cytokinerelease from cancer cells. S1P is known to elicit significant release ofIL-8 into the cell-conditioned media from cancer cells. Addition of themouse control anti-S1P mAb reduced IL-8 release from ovarian cancercells in a concentration-dependent manner. The two humanized variantshuMAbHC_(CysAla)LC₃ (LT1007) and huMAbHC_(CysAla)LC₅ (LT1009) exhibitedgreater reduction of IL-8 release compared to HuMAbHCLC₃ (LT1004) andhuMAbHCLC₅ (LT1006).

Example 17 In vivo Efficacy of Murine mAb (Sphingomab) vs, Humanized mAb(Sonepcizumab) in an Animal Model of Neovascularization

Choroidal neovascularization (CNV) refers to the growth of new bloodvessels that originate from the choroid through a break in the Bruchmembrane into the sub-retinal pigment epithelium (sub-RPE) or subretinalspace in the eye. CNV is a major cause of visual loss in maculardegeneration and other ocular conditions. A mouse model of CNV is usedin this example for evaluation of mAbs against S1P.

The humanized antibody variants and the murine antibody were comparedfor their ability to inhibit neo-vascularization in the CNV animal modelof AMD as shown in FIG. 13. Mice were administered 0.5 ug twice (Day 0and Day 6) of the murine (Mu; LT1002), the humanized variants [LC3(LT1004), LC5 (LT1006), HC_(CysAla)LC3 (LT1007) and HC_(CysAla)LC5(LT1009)] or the nonspecific mAb (NS) by intravitreal administration andthen subjected to laser rupture of Bruchs membrane. Mice were sacrificed14 days post laser surgery. Control mice were treated with aqueousbuffer (PBS) or an isotype-matched non-specific antibody. Three of thehumanized variants inhibited angiogenesis essentially equivalently tothe murine antibody as assessed by measurement of CNV area. CNV lesionvolumes are represented as means±SEM. The humanized variant containing 5backmutations in the light chain and with a cysteine mutation in CDR2 ofthe heavy chain (huMAbHC_(CysAla)LC₅; LT1009) markedly suppressedneovascularization. This difference was highly statisticallysignificant.

For the induction of CNV, mice were anesthetized with a mixture ofketamine (14 mg/kg) and xylazine (30 mg/kg) in sterile salineadministered intraperitoneally at a dose of 5 μL per 20 g of bodyweight. Their pupils were then dilated with one drop each of ophthalmictropicamide (0.5%) and phenylephrine (2.5%). An argon green ophthalmiclaser (Oculight GL 532 nm, Iridex Corporation, Mountain View, Calif.)coupled to a slit lamp set to deliver a 100 msec pulse at 150 mW with a50 μm spot size will then be used to rupture Bruch's membrane in threequadrants of the right eye located approximately 50 μm from the opticdisc at relative 9, 12 and 3'oclock positions. The left eye served asuninjured control in all cases.

The morphometric and volumetric CNV lesions were measured as follows.Two weeks after laser induction of CNV, the animals were euthanized byoverdose of ketamine-xylazine mixture, then undergo whole body perfusionvia cardiac puncture with 6 ml 4% paraformaldehyde in PBS, pH 7.5,(fixative) as previously described (Sengupta et al., 2003). The eyeswill then be enucleated, punctured with a 27 g needle 1 mm posterior tothe limbus, and immersed in fixative for 1 hr at room temperature, thenwashed 2× by immersion in PBS for 30 min. The eyes will then bedissected to isolate the posterior segment consisting of the retinalpigment epithelium, the choriocapillaris and the sclera. This tissue wasthen permeabilized and reacted with rhodamine-conjugated R. communisagglutinin I (Vector Laboratories, Burlingame, Calif.) to detect the CNVlesion as previously described (Sengupta et al., 2003; Sengupta et al.,2005). The posterior cups was then cut with 4-7 radial slices, andmounted flat on microscope slides with a drop of Vectashield anti-fademedium (Vector Laboratories, Burlingame, Vt.) for digital image captureby epifluorescence Zeiss Axioplan 2 with RGB Spot high-resolutiondigital camera) and laser scanning confocal microscopy (BioRad MRC 1024,BioRad Corporation, Temecula, Calif.).

Captured digital images were evaluated morphometrically using ImageJsoftware (Research Services Branch, National Institutes of Health,Bethesda, Md.). Images were split into separate RGB channels foranalysis of the red and green channels as follows: 1) a calibration forthe specific objective and microscope was applied to set thepixel-to-length ratio; 2) a threshold was applied using the Otsualgorithm; 3) images will be made binary; 4) a region-of-interest (ROI)was outlined to include the entire lesion area; 5) a particle analysiswas performed to quantify the pixel area above the threshold levelwithin the ROI. For volumetric analysis, the process was similar to thatdescribed above, except that a z-series capture was used. The sum oflesion area throughout the z-series was then multiplied by the zthickness (typically 4 μm) to obtain the lesion volume.

Drug products tested in this model were LT1002 (murine mAb to S1P;Sphingomab™); LT1004 (humanized mAb), LT1006 (humanized mAb), LT1007(humanized mAb) and LT1009 (humanized mAb; Sonepcizumab™). Also includedwere saline vehicle and non-specific antibody (NSA) controls. As shownin FIG. 13, both the murine mAb LT1002 (Sphingomab™) and the humanizedmAb LT1009 (Sonepcizumab™) significantly decreased lesion size in thismouse model of CNV. All mAbs tested showed approximately 80-98%reduction of lesion size, which was significant (p<0.001 vs. saline) inall cases. In addition, LT1007 and LT1009 also showed significantinhibition (p<0.05) compared to non-specific antibody control. Percentinhibition of lesion size was approximately 80% for LT1002 (murine), 82%for LT1004 (humanized), 81% for LT1006 and 99% for LT1009. Thus, LT1009was the humanized mAb variant most active in this in vivo model ofneovascularization.

Example 18 Determination of the Sonepcizumab Dose Response

Mice (n=10) received a single, bilateral intravitreal injection ofescalating doses of sonepcizumab (0.085, 0.85, 1.7 or 5 μg/eye) or ahigh dose nonspecific (NS) antibody (3.0 μg/eye) one day prior tolaser-induced rupture of Bruch's membrane. Fourteen days after laserrupture, mice were anesthetized and perfused with fluorescein-labeleddextran and choroidal flatmounts were prepared for analysis of CNVlesion size.

In this study, the effect of sonepcizumab dose amount and dose intervalon CNV inhibition were examined using another validated method ofquantifying CNV area in which animals were perfused withfluorescein-labeled dextran just before sacrifice. Sonepcizumab induceda dose-dependent reduction in the area of CNV resulting in a maximalinhibition of approximately 50%, at a dose of 5 μg/eye. This reductionwas significant (p<0.0001 compared to non-specific antibody controlusing an unpaired t-test). In the dosing frequency study, similarefficacy was observed between groups treated with Sonepcizumab at asingle timepoint (day 0) or at multiple timepoints (days 0 and 7) overthe 14-day study.

The maximal inhibition of approximately 50% seen with Sonepcizumabtreatment (5 ug/eye) compares favorably with previously published datain the same model and conducted by the same investigator demonstratingthe reduction in CNV area by the VEGF-Trap (4.92 μg/eye). Saishin, etal. J Cell Physiol, 2003. 195(2): p. 241-8. “Traps” (RegeneronPharmaceuticals, Inc.) are fusions between two distinct receptorcomponents and the Fc region of an antibody molecule called the Fcregion and the VEGF-Trap is being pursued for ocular disease and cancerby Regeneron. A comparison of these two independent studies reveals thatthe reduction in CNV lesion size by Sonepcizumab was 20 percentagepoints greater than that observed with the VEGF-Trap. Thus, these datanot only confirm our preliminary findings regarding the ability of ananti-S1P therapy to reduce lesion formation in murine model of CNV, butthey also demonstrate the increased efficacy of the humanized antibody,sonepcizumab, to inhibit CNV lesion formation and provide insight intoan anti-permeability effect.

Example 19 Efficacy of Sonepcizumab in Reducing the Development ofRetinal Neovascularization in a Murine Model of Retinopathy ofPrematurity

C57BL/6 mice (n=7) were placed in 75% oxygen at day 7 of life and at day12 of life were returned to room air and given an intraocular injectionof 5 μg of sonepcizumab in one eye and vehicle in the contralateral eye.At day 17, the mice received an intraocular injection of anti-PECAMantibody labeled with FITC and after 8 hours, mice were euthanized andeyes were removed and fixed in PBS-buffered formalin at room temperaturefor 5 hours. Retinas were dissected and washed with phosphate-bufferedsaline containing 0.25% Triton X-100 and whole mounted. Slides wereviewed with a Nikon Fluorescence Microscope and the area of retinal NVper retina was measured by image analysis.

Consistent with the reduction in CNV observed in the murine laserrupture model, we also observed a dramatic reduction in CNV in a murinemodel of retinopathy of prematurity (ROP). Intravitreal administrationof Sonepcizumab (5.0 μg/eye) resulted in a nearly 4-fold reduction inretinal neovascularization compared to saline control. These dataconfirm the efficacy of sonepcizumab to inhibit pathological ocularangiogenesis in both the retinal and choroidal vascular beds whetherinduced via ischemia or rupture of Bruch's membrane.

Example 20 Effect of Sonepcizumab on VEGF-Induced Angiogenesis in aMatrigel Plug Assay

Neovascularization in vivo was performed using the GFR Matrigel plugassay as described in Staton, et al., Int J Exp Pathol, 2004. 85(5): p.233-48. 4-6 week old nu/nu mice were injected in the left flank with 500uL of ice-cold GFR Matrigel. The GFR Matrigel was injected either alone(control) or after addition of 10 ug/mL VEGF supplemented with 100 ug/mlheparin. Groups consisted of 3 animals for control and sonepcizumabtreatment. Animals were treated with the saline or sonepcizumab (10mg/kg) 1 day prior to the implantation of GFR Matrigel and doses wereadministrated i.p. every 72 hrs for the duration of the experiment.After 12 days animals were sacrificed; the plugs were excised andimmediately fixed in zinc and formalin-free fixative overnight, embeddedin paraffin and sectioned (5 um). Paraffin-embedded sections were thenstained for CD31 (Pharmingen). Images (9 images per section, 3 sectionsper plug) were taken by digital camera at 20× magnification and the CD31positive staining was then quantified by PhotoShop 6.0 program andexpressed as angiogenesis score (pixel²) by ImageJ.

The anti-angiogenic effects of sonepcizumab were evident in thisMatrigel plug assay. As expected extensive neovascularization (approx.5.75× that seen in untreated control lacking VEGF or sonepcizumab) wasinduced in the Matrigel plugs supplemented with 10 ug/ml VEGF.Importantly, systemic i.p. treatment with sonepcizumab prior to Matrigelinjection prevented nearly 80% of this VEGF-stimulated increase incellularity and microvessel density. This reduction is significant(p<0.05 compared to VEGF alone) and confirms the potent anti-angiogenicactivity of sonepcizumab when administered systemically to animals andstrongly suggest that sonepcizumab is capable of significantlyinhibiting VEGF induced angiogenesis. This finding is consistent withdata from Lpath's oncology program whereby that S1P antibody reducedserum levels of several angiogenic factors, including VEGF, in a murineorthotopic breast cancer model.

A primary component of blood vessel growth associated with AMD is therecruitment of pericytes which ensheath and support the growingendothelial tube. Jo, et al., Am J Pathol, 2006. 168(6): p. 2036-53.Transgenic mouse studies have shown that VEGF and PDGF-B are the primaryfactors that stimulate infiltration and differentiation of pericytesleading to blood vessel maturation and stabilization. Guo, et al., Am JPathol, 2003. 162(4): p. 1083-93; Benjamin, L. E., I. Hemo, and E.Keshet, Development, 1998. 125(9): p. 1591-8. Importantly, S1P promotestrans-activation of VEGF and PDGF. Therefore, the ability ofsonepcizumab to indirectly neutralize these growth factors suggests thatsonepcizumab could prevent abnormal blood vessel growth during AMD.

Example 21 Sonepcizumab Significantly Reduces Vascular Leakage FollowingLaser Rupture of Bruch's Membrane

The efficacy of sonepcizumab, administered to inhibit vascular leakage(in addition to inhibiting neovascularization as shown above) wasevaluated in a murine model of laser rupture of Bruch's membrane.

C57BL/6 mice (n=10) underwent laser rupture of Bruch's membrane in 3locations in each eye and were given an intraocular injection of 5 μg ofsonepcizumab in one eye and vehicle in the contralateral eye. At oneweek after laser rupture, the mice were given an intraperitonealinjection of 12 μl/g body weight of 1% fluorescein sodium and wereeuthanized 5 minutes later. The eyes were removed and fixed inPBS-buffered formalin at room temperature for 5 hours. Then the retinaswere dissected, washed, and incubated with primary anti-PECAM-1. Theretinas were then washed, incubated with secondary antibody (goatanti-rat IgG conjugated with rhodamine), and then flat mounted.

Quantification of CNV lesion area is measured by PECAM-1 staining.Quantification of vascular leakage is measured by fluorescein sodiumstaining. The total area of leakage from CNV=CNV+leakage (green)−area ofCNV (red). Values represent the mean±SEM for n=10 mice/group. The areaof choroidal neovascularization (stained by PECAM-1) was approximately0.015 mm² for animals treated with LT1009 and approximately 0.03 mm² forsaline-treated control animals. This is a 50% reduction inneovascularization (p-0.018). The area of leakage from choroidalneovascularization (stained by fluorescein) was approximately 0.125 mm²for animals treated with LT1009 and approximately 0.2 mm² forsaline-treated control animals. This is approximately a 38% reduction(p-0.017) in blood vessel leakage.

Representative immunohistochemical images of the reduction in choroidalneovascularization and vascular leakage in mice treated with 5.0 μg/eyeof Sonepcizumab or PBS control are consistent with these results. Thus,in addition to reducing CNV, sonepcizumab significantly reduced vascularleakage following laser rupture of Bruch's membrane retinal edema, whichplays a major role in the loss of visual acuity, is associated with: (i)choroidal neovasculature leakage in AMD and (ii) the breakdown of theblood-retinal barrier in diabetes. Gerhardt, H. and C. Betsholtz, CellTissue Res, 2003. 314(1): p. 15-23 Sonepcizumab reduces pathologicalblood vessel formation in the eye as well as vascular leakage thatresults in retinal edema. These findings are consistent with the datagenerated from the CNV-area-quantification experiment in which mice wereperfused with fluorescein-labeled dextran. CNV quantification via thismethod surely is affected by vascular permeability. The highly favorableresults argue for an anti-permeability effect in the choroidal vascularbed. Given these data, we believe that sonepcizumab has the potential tobe a monotherapy. The possibility of a synergistic effect with currentpan-VEGF-A blocking agents also exists.

Example 22 Reduction of Macrophage Infiltration in the Retina AfterTreatment with Antibody to S1P

Age-related macular degeneration (AMD) is a disease associated withaging that gradually destroys sharp, central vision. There are two maintypes of macular degeneration. The dry or atrophic form which accountsfor 85-90% of AMD cases, and the wet form of AMD characterized by thegrowth of abnormal blood vessels. Dry macular degeneration is diagnosedwhen yellowish spots known as drusen begin to accumulate from depositsor debris from deteriorating tissue primarily in the area of the macula.Gradual central vision loss may occur. There is no effective treatmentfor the most prevalent atrophic (dry) form of AMD. Atrophic AMD istriggered by abnormalities in the retinal pigment epithelium (RPE) thatlies beneath the photoreceptor cells and normally provides criticalmetabolic support to these light-sensing cells. Secondary to RPEdysfunction, macular rods and cones degenerate leading to theirreversible loss of vision. Oxidative stress, ischemia, formation ofdrusen, accumulation of lipofuscin, local inflammation and reactivegliosis represent the pathologic processes implicated in pathogenesis ofatrophic AMD. Of these processes, inflammation is emerging as a keycontributor to tissue damage. Macrophage infiltration into the macula ofpatients with dry AMD has been demonstrated to be an important componentof the damaging inflammatory response. Therefore an agent which couldmitigate macrophage infiltration would be a valuable therapeutic, asinhibition of macrophage infiltration would likely diminish maculartissue damage. Such an agent may also decrease the rate at which dry AMDconverts to wet AMD.

In a model of ischemic and inflammatory retinopathy, a 55% inhibition ofmacrophage infiltration has now been demonstrated after treatment withan anti S1P antibody. These data were generated using the wellestablished murine oxygen induced retinopathy model (also known as theretinopathy of prematurity (ROP) model). Specifically, C57BL/6 mice wereplaced in 75% oxygen on day 7 of life and at day 12 of life werereturned to room air and given an intraocular injection of 5 μg ofhumanized anti S1P antibody (LT1009, Sonepcizumab™) in one eye andvehicle in the fellow eye. At day 17 of life, the mice received anintraocular injection of FITC-labeled antibody to F4/80 (apan-macrophage marker) and after 8 hours, mice were euthanized. Theglobes were removed and fixed in PBS-buffered formalin at roomtemperature for 5 hours. Retinas were dissected and washed withphosphate-buffered saline containing 0.25% Triton X-100 and wholemounted. Slides were viewed with a Nikon Fluorescence Microscope andretinal macrophages were quantified. The results are shown in Table 7below.

TABLE 7 Reduction in macrophage infiltration in the retina by treatmentwith humanized monoclonal antibody to S1P # of macrophages per retina %reduction in macrophage density Saline control S1P antibody Salinecontrol S1P antibody 2513 ± 115 1136 ± 33 100 ± 0.5 55.4 ± 1.3 P < 0.001P < 0.0001

On the basis of these data and the known role of macrophages in thepathogenesis of dry AMD it is believed that anti-S1P antibodiesrepresent an effective therapeutic agent for the treatment of dry AMD.

Example 23 Response of SC COLO205 Colorectal Tumor Xenograft in Nude NCrMice to Treatment with 25-75 mg/kg LT1009, Alone and in Combination withAvastin or Paclitaxel

The objective of this study was to determine the efficacy of LT1009,alone and in combination with other anti-cancer agents, to retard theprogression of human colorectal (COLO205) carcinoma tumors graftedsubcutaneous (sc) and established in female Ncr (nu/nu) mice.

Nude mice were implanted sc near the right flank with one fragment permouse of COLO 205 tumor from an in vivo passage. All treatments wereinitiated the day when 60 mice in each experiment established tumorsranging in size from approximately 100 to 200 mm3. The mice (n=10 pergroup) were then treated with either 25 mg/kg of LT1009, 50 mg/kgLT1009, 40 mg/kg Avastin, 50 mg/kg LT1009 plus 40 mg/kg Avastin, 15mg/kg Paclitaxel or vehicle (saline). 25 or 50 mg/kg LT1009 and salinewere administered ip once q3d in a volume of 0.1 mL/20 g body weight forthe duration of the experiment. Avastin was administered iv at a dosageof 40 mg/kg/dose on a q7d schedule, injected in a volume of 0.1 mL/20 gbody weight. Paclitaxel (positive control), was administered iv at adosage of 15 mg/kg/dose on a q1d×5 schedule, injected in a volume of 0.1mL/10 g body weight. On Day 21, the dose of 25 mg/kg LT1009 wasincreased to 75 mg/kg LT1009 for the duration for the study.

Animals were observed daily for mortality. Tumor dimensions and bodyweights were collected twice weekly starting with the first day oftreatment and including the day of study termination. When the mediantumor in the vehicle-treated control group in each study reachedapproximately 4,000 mg, the study was terminated. Tumors from eachanimal were harvested, wet weights were recorded, tumors were processedfor determination of microvascular densities (MVD) by CD-31 staining.Tumor weights (mg) were calculated using the equation for an ellipsoidsphere (l×w²)/2=mm³, where l and w refer to the larger and smallerdimensions collected at each measurement and assuming unit density (1mm³=1 mg).

TABLE 8 Numerical summary of findings -Colo205 % Reduction Final TumorCompared to Vehicle- Treatment Weights (mg) Treated Mice Vehicle 3047.25— 50 mg/kg LT1009 2071.17 32% 25/75 mg/kg LT1009 2465.60 20% Avastin1967.90 35% Avastin + 50 mg/kg 1614.40 48% LT1009 Paclitaxel 0 100% 

50 mg/kg LT1009 substantially inhibited tumor progression (p<0.018), asmeasured by final tumor weights, by 32% when compared to tumors fromsaline-treated animals. 25/75 mg/kg LT1009 was also effective inreducing final tumor weights by 20%; however, this reduction was notstatistically significant. 50 mg/kg LT1009 was as effective as Avastinin reducing final tumor weights (32% versus 35% reduction,respectively). The combination of LT1009 and Avastin was more effectivethan either agent alone, demonstrating a 48% reduction in tumor weightswhen compared to saline-treated animals. Thus the effects of LT1009 andAvastin appear to be additive. The positive control, Paclitaxel,completely eliminated the pre-established tumors.

Example 24 Response of SC HT29 Colorectal Tumor Xenograft in Nude NCrMice to Treatment with 50 mg/kg LT1009, Alone and in Combination withAvastin and 5-FU

The objective of this study is to evaluate the antitumor efficacy ofLT1009, alone and in combination with other anti-cancer agents, againsthuman HT29 colon tumor xenografts implanted sc in female athymicNCr-nu/nu mice.

Nude mice were implanted sc near the right flank with one fragment permouse of HT29 tumor from an in vivo passage. All treatments wereinitiated the day when 60 mice in each experiment established tumorsranging in size from approximately 100 to 200 mm³. There were ten miceper treatment group. 50 mg/kg LT1009 and saline were administered ip q2din a volume of 0.1 mL/20 g body weight for the duration of theexperiment. 75 mg/kg 5-FU and 20 mg/kg Avastin were administered ip andiv at a dosage of 75 mg/kg/dose and 20 mg/kg/dose, respectively, q4d,injected in a volume of 0.1 mL/10 g body weight. The first dose ofLT1009 consisted of 100 mg/kg administered iv.

Animals were observed daily for mortality. Tumor dimensions and bodyweights were collected twice weekly starting with the first day oftreatment and including the day of study termination. When the mediantumor in the vehicle-treated control group in each study reachedapproximately 4,000 mg, the study was terminated. Tumors from eachanimal were harvested, wet weights were recorded, and tumors wereprocessed for determination of MVD by CD-31 staining. Tumor weights (mg)were calculated using the equation for an ellipsoid sphere (l×w²)/2=mm³,where l and w refer to the larger and smaller dimensions collected ateach measurement and assuming unit density (1 mm³=1 mg).

TABLE 9 Final Tumor Weights- HT29 % Reduction Final Tumor Significancecompared to Vehicle- Treatment Weights (mg) (p-value) Treated MiceVehicle 2723.67 — — LT1009 2390.63 1.00 13% Avastin 1927.44 0.39 30%LT1009 + 1624.90 0.001 41% Avastin 5-FU 1963.71 0.099 28% LT1009 +1948.00 0.049 29% 5-FU

50 mg/kg LT1009 reduced tumor progression, as measured by tumor weights,by 13% while Avastin reduced tumor weights by 30% when compared totumors from saline-treated animals. The combination of LT1009 andAvastin was more effective than either agent alone demonstrating astatistically significant 41% reduction in tumor weights when comparedto saline-treated animals. Treatment with 5-FU reduced tumor weights by28%. 5-FU showed minimal additive effect with LT1009 demonstrating a 29%inhibition of final tumor weights.

Example 25 Response of SC DU145 Prostate Tumor Xenograft in Nude NCrMice to Treatment with 50 mg/kg LT1009, Alone or in Combination withAvastin or Paclitaxel

The objective of this study was to determine the efficacy of LT1009,alone and in combination with other anti-cancer agents, to retard theprogression of human prostate (DU145) carcinoma tumors graftedsubcutaneous (sc) and established in female Ncr (nu/nu) mice.

Nude mice were implanted sc near the right flank with one fragment permouse of DU145 tumor from an in vivo passage. All treatments wereinitiated the day when 60 mice in each experiment established tumorsranging in size from approximately 100 to 200 mm³. The mice (n=10/group)were then treated with either 50 mg/kg of LT1009, 20 mg/kg Avastin, 7.5mg/kg Paclitaxel, 50 mg/kg LT1009 plus 20 mg/kg Avastin, 50 mg/kg LT1009plus 7.5 mg/kg Paclitaxel or vehicle (saline). 50 mg/kg LT1009 andsaline were administered ip q2d in a volume of 0.1 mL/20 g body weightfor the duration of the experiment. Paclitaxel and Avastin wereadministered iv and ip at a dosage of 7.5 mg/kg/dose and 20 mg/kg/dose,q1d×5 and q4d, respectively, injected in a volume of 0.1 mL/10 g bodyweight. The first dose of LT1009 consisted of 100 mg/kg administered iv.

During the course of the study tumor growth was monitored by measuringthe sc tumors on three axes and calculating the volume. At the end ofthe study final tumor weights and volumes were determined and then themice were sacrificed, the tumors harvested. Microvascular densities(MVD) of the tumors were then determined by CD-31 staining.

TABLE 10 Numerical summary of findings- DU145 % Reduction Final TumorSignificance compared to Vehicle- Treatment Weights (mg) (p-value)Treated Mice Vehicle 2703 — — LT1009 2242 0.00 28% Avastin 578 0.00 79%LT1009 + 676 0.00 75% Avastin Paclitaxel 539 0.00 80% LT1009 + 373 0.0084% Paclitaxel

50 mg/kg LT1009 significantly (p<0.00) reduced tumor progression, asmeasured by final tumor weights, by 28%. Avastin and Paclitaxel alsosignificantly (p<0.00) reduced final tumor weights by 80% when comparedto tumors from saline-treated animals. LT1009 did not significantlyincrease the anti-tumor activity, as measured by final tumor volumes, ofAvastin or Paclitaxel.

Example 26 Response of RPMI 8226 Human Myeloma Tumor Xenograft in CB17SCID Mice to Treatment with 25 mg/kg or 50 mg/kg LT1009, Alone and inCombination with Bortezomib

The objective of this study is to evaluate the antitumor efficacy ofLT1009, alone and in combination with the anti-cancer agent Bortezomib,against human RPMI human myeloma tumor xenografts implanted sc in femaleCB17 SCID mice.

Nude mice (CB17 SCID, aged 4-5 weeks, weight 18-22 gm, female miceobtained from Harlan) were injected sc with RPMI 8226 cells harvestedfrom tissue culture (˜1×10⁷ cells/mouse). When tumors grew toapproximately 100 mm³ in size, animals were pair-matched by tumor sizeinto treatment and control groups (10 mice per group). Initial dosingbegan Day 1 following pair-matching. Animals in all groups were dosed byweight (0.01 ml per gram; 10 ml/kg). LT1009 in vehicle was administeredby intraperitoneal (IP) injection once every three days until studycompletion (Q3D to end). Bortezomib was administered by intravenousinjection via tail vein once every three days for six treatments(Q3D×6). To serve as a negative control, LT1009 vehicle (0.9% saline)was administered IP on a Q3D to end schedule.

Individual and group mean tumor volumes±SEM are recorded twice weeklyuntil study completion beginning Day 1. Final mean tumor volume±SEM foreach group are reported at study completion; animals experiencingpartial or complete tumor regressions or animals experiencing technicalor drug-related deaths are censored from these calculations.

TABLE 11 Final Tumor Volumes- RPMI % Reduction Final Tumor compared toVehicle- Treatment Weights (mg) Treated Mice Vehicle 2083 0 Bortezomib1664 20% 25 mg/kg LT1009 1860 11% 50 mg/kg LT1009 1978  5% 50 mg/kgLT1009 + 1832 12% Bortezomib

Example 27 Efficacy of Agents that Decrease the Effective Concentrationof Bioactive Lipids in a Murine Experimental Allergic Encephalomyelitis(EAE) Model of Multiple Sclerosis

EAE is an experimental autoimmune disease of the central nervous system(CNS) (Zamvil et al, (1990) Ann. Rev. Immunol., 8:579 and is a diseasemodel for the human autoimmune condition, multiple sclerosis (MS)[Alvord et al, Experimental Allergic Model for Multiple Sclerosis, NY511 (1984)]. It is readily induced in mammalian species [for example,SJL/J mice are a susceptible strain of mice (H-2^(S))] by immunizationsof myelin basic protein purified from the CNS (e.g., an emulsion ofguinea pig or bovine spinal column) or an encephalitogenic proteolipid(PLP) or a peptide fragment of myelin oligodendrocyte glycoprotein(MOG₃₅₋₅₅). Experimental allergic encephalomyelitis (EAE) in mice,induced by injection of white matter, is a useful model of CNSinflammation, and has been used in the study of multiple sclerosis(Spahn et al. 1999; also see over 40 papers on various mouse models ofEAE by Howard Weiner).

Animals with EAE develop an acute paralytic disease and an acutecellular infiltrate is identifiable within the CNS. Thus in addition toserving as a standard model for MS, this model has also been used todetermine T-cell infiltration into the CNS. T-lymphocytes are rarelyfound in the normal CNS, but during MS, HIV induced encephalomyelitis orother CNS inflammatory conditions these cells are present. Symptomsobserved include muscle weakness, paralysis, and lack of coordination.

Experimental protocol—the following experiments were conducted in thelaboratory of Dr. Howard Weiner in collaboration with Lpath, Inc. Apeptide fragment of myelin oligodendrocyte glycoprotein (MOG₃₅₋₅₅;MEVGWYRSPFSRVVHLYRNGK) is used to cause experimental EAE in mice.Mendel, I. et al., A myelin oligodendrocyte glycoprotein peptide inducestypical chronic experimental autoimmune encephalomyelitis in H-2b mice:fine specificity and T cell receptor V beta expression ofencephalitogenic T cells, Eur J Immunol. July 1995;25(7):1951-9. EAE wasinduced in mice by immunization with a peptide corresponding to aminoacids 35-55 of myelin oligodendrocyte glycoprotein (MOG) peptide (MOG₃₅₅₅) to induce chronic experimental autoimmune encephalomyelitis (EAE).Following immunization with MOG₃₅₋₅₅, mice develop an acute episode ofEAE that is followed by a gradually developing progressive diseasethought to model several features of progressive multiple sclerosis.Mice were treated with antibody to S1P and treated mice were followed tostudy the effects of S1P-specific antibody on the clinicalmanifestations of this acute model of EAE. At the end of the experiment,treated mice were also used to analyze the effect of anti-S1Padministration on the immune response.

In a first set of experiments, using 10 mice per group with an averageweight of 20 gr, EAE was induced in C57BL/6J mice with 150 ug/mouseMOG₃₅₋₅₅ in CFA along with 150 pg/mouse pertussis toxin on days 0 and 2.Anti-S1P antibody LT1002 (Sphingomab™) was administered i.v. at a dosageof 75 mg/Kg on day-1, followed by i.p. dosing at 25 mg/Kg every 2 days.Treated mice were followed for 25 days to study the effects ofS1P-specific antibodies on the clinical manifestations of this acutemodel of EAE. Clinical manifestations of the disease include flaccidtail, and limb paralysis which may be scored to give an objectiveevaluation of clinical symptoms. The standard evaluation of diseaseseverity in the EAE model measures clinical behavior on a 0-6 scale: 0)normal; 1) flaccid tail; 2) abnormal gait, hind leg weakness; 3) partialparalysis, severe ataxia; 4) minimal hind leg movement after painfulstimulus; 5) no hind leg movement; 6) moribund state with little or nomovement. Means were compared between groups to determine the effect oftreatment on clinical scores and body weight gain. Statisticalsignificance of clinical scores and weight were resolved usingbiostatistical analysis.

At day 17, two representative mice were sacrificed to study the cellularimmune response (proliferation and cytokines) and to analyze CNSpathology. Spinal cords were dissected and sectioned. Sections werestained with hematoxylin and eosin (H&E) to reveal inflammatory cells,with Luxol to visualize myelin, or with silver stain to visualize axons.Total levels of CD4+FoxP3+T_(reg) cells were evaluated by FACS analysisof blood samples taken from the tail on day 17. At day 25, treated micewere analyzed to see the effect of anti-S1P administration on the immuneresponse.

Administration of anti-S1P antibody (LT1002; Sphingomab™) was found tolead to a significant inhibition of EAE development (p<0.001). This canbe seen in as a decrease in EAE symptoms, scored as described above,which is shown in FIG. 1. After antibody treatment, the EAE scores leveloff at approximately 2 (abnormal gait, hind leg weakness) on the scaleof disease severity, whereas the untreated control animals had an EAEseverity score of approximately 3 (partial paralysis, severe ataxia).This clinical effect is confirmed histologically, with a quantifiabledecrease in demyelination (less than 1% demyelination inantibody-treated animals vs. 9% demyelination in untreated controls withEAE, approximately a 92% decrease after treatment), decrease in axonalloss (less than 2% axonal loss in antibody-treated mice vs. 18% axonalloss in untreated control animals with EAE, approximately a 91% decreaseafter treatment) and decrease of about 85% in number of inflammatorycells/mm² in spinal cords of antibody-treated animals compared tountreated controls with EAE.

In addition, anti-S1P administration led to a decrease in the number ofcirculating lymphocytes and spleen CD4+T cells). Circulating lymphocytestotaled approximately 10% in antibody-treated animals, and about 13.5%in control animals with EAE. This decrease was significant andrepresents approximately a 26% decrease in circulating lymphocytes afterantibody treatment. Spleen CD4+T cells totaled approximately 7.6% oflymphocytes in spleen in antibody-treated animals, as compared toapprox. 11.7% of lymphocytes in control animals. This decrease was alsosignificant and represents about a 35% decrease after antibodytreatment.

A class of specialized T cells that inhibit the proliferation andactivation of effector T cells are known as suppressor or regulatory Tcells (T_(regs)). A major class of T_(regs) is CD4⁺CD25⁺T cells whichplay a role in the maintenance of self tolerance. Depletion ofCD4+CD25+T_(reg) in mice results in the onset of systemic autoimmunediseases, and under such conditions, murine EAE increased in severity;thus it is believed that impairment of T_(reg) cells may contribute todisease. Kumar et al., (2006) J. Neuroimm. 178:184; Sakaguchi et al.(1985) and Stephens et al., (2005), both as cited in Kumar et al. Kumaret al. also found a reduction or loss of suppressive activity of T_(reg)cells from MS patients.

CD4⁻CD25⁺T_(regs) express the transcription factor Foxp3 gene atrelatively high levels. CD25+ and Fox P3+ together are specific markersfor T_(reg) cells. Anti-S1P administration to mice with EAE was found tobe associated with a significant increase in CD4⁺CD25⁺Foxp3⁺T_(reg) inspleen and a similar but statistically nonsignificant increase incirculating CD4⁺CD25⁺Foxp3⁺T_(reg) cells. These results indicate anincrease in T_(reg) cells after antibody treatment.

Injection of synthetic MOG peptide (amino acids 35-55 of myelinoligodendrocyte glycoprotein, referred to as MOG₃₅₋₅₅) causes mice todevelop significant specific T cell responses in addition toneurological symptoms. Spahn et al., (1999) Eur. J. Immunol29:4060-4071. Anti-S1P administration was associated with a significantdecrease in this proliferative recall response to MOG₃₅₋₅₅. Mice wereprimed by injections of MOG peptide. The spleens were removed andhomogenized, and splenocytes were pulsed with different amounts of MOGpeptide. Subsequently, cells were pulsed with radiolabel and incubatedbefore cells were harvested and label incorporation was assessed byscintillation counting. T cell priming to MOG was found to be reducedafter S1P antibody treatment. As measured in cpm, the recallproliferative response was decreased by approximately 36%, 38% and 22%after anti-S1P antibody treatment (at 4 ug/ml, 20 ug/ml and 100 ug/ml ofMOG₃₅₋₅₅, respectively). This blockade of lymphocyte proliferation bythe S1P antibody suggests that the antibody is able to block theautoimmune response to MOG in these mice.

Splenocytes from anti-S1P-treated mice secreted lower levels of IL-17and IFNγ and higher levels of IL-10 upon stimulation with MOG₃₅₋₅₅.Using methods essentially as in Spahn et al. (1999) Eur. J. Immunol.29:4060-4071, the protective cytokine IL-10 was increased by antibodytreatment, compared to control splenocytes from untreated animals, whilethe deleterious cytokines are decreased.

Thus it has been shown that treatment with antibody to S1P decreasessymptoms of EAE, a well-accepted animal model of MS. Paralysis andweakness are decreased, and this is supported by histological findingsshowing neurodegeneration, demyelination and inflammation in the CNS.Anti-S1P administration also led to a significant decrease in the numberof circulating lymphocytes and spleen CD4+T cells, indicating the effectof this antibody on lymphocyte trafficking. Anti-S1P administration wasalso associated with a significant increase in regulatory T cells. Thusthe anti-S1P antibody acts through several mechanisms, all of which arebelieved to be useful in reduction of disease indicators in this modelof MS.

Anti-S1P antibody (LT1002; Sphingomab™) is also expected to beefficacious in the SJL/PLP (relapsing-remitting) interventional model ofMS. EAE is induced in SJL/J mice (10 mice/group) by immunization with apeptide corresponding to the 139-151 aa region of the proteolipidprotein (PLP139-151). See Webb et al. (2004) J. Neuroimmunol.153:108-121. Following immunization with PLP139-151, SJL/J mice developa disease thought to model several features of multiple sclerosis.Antibody treatment is given after the neurological symptoms appear. Thesame doses of the anti-S1P antibody (LT1002) will be used as in theexperiment above: 75 mg/kg on day 17 i.v. (peak of disease) followed bya dose of 25 mg/kg every two days.

Example 28 Anti-S1P Antibodies LT1002 and LT1009 Decrease LymphocyteCounts when Administered to c57/bl6 mice or Cynomologous Monkeys,Respectively

Murine Studies with LT1002

The purpose of this study was to determine the toxicity andtoxicokinetic profile of the murine anti-S1P monoclonal antibody,LT1002, following daily administration to C57/BL6 mice. The study wasconducted by an independent contract laboratory organization, LABResearch, Inc. The LT1002 dosing solutions were administered for 28consecutive days to animals in each group by bolus intravenous injectionvia the tail vein (Days 1-14) and then by bolus intraperitonealinjection (Days 15-28), over a period of approximately 0.5-1.0 minute.The treated group animals were dosed with LT1002 at 30, 75 or 200 mg/kg(n=6 per group) and compared to animals treated with PBS as a saline(vehicle) control group.

During the study, animals were monitored for effects on mortality,clinical condition, body weight and food consumption. Blood samples werecollected from a subgroup of animals at necropsy for assessment ofhematology, coagulation and clinical chemistry. Study animals wereeuthanized and subjected to a necropsy examination. Selected organs wereweighed and a full list of tissues was retained. A histopathologyexamination was performed on the full tissue list from all control andhigh dose animals (200 mg/kg/day) and all abnormalities, while targetorgans were examined on lower dose groups. Blood samples were collectedfrom the toxicokinetic animals (3 animals/sex/group/time point) on Days1, 14 and 28 and the animals were euthanized and discarded withoutexamination.

Mean lymphocyte counts were significantly (p<0.001) reduced in allLT1002-treated dosing groups with a weak dose-response effect. Theaverage lymphocyte counts (10⁹ cells/L±SD) for the control, untreatedgroup were 2.9±1.3 (n=6), which were reduced in the 30, 75 and 200 mg/kggroups, respectively to 0.856±0.426 (n=6), 0.902±0.269 (n=5) and0.638±0.262 (n=4). These data are consistent with those in the exampleabove, showing that, in the murine EAE model of multiple sclerosis,LT1002 caused substantial reductions in lymphocyte counts correlatedwith reductions in axonal degeneration, demyelination and infiltrationof inflammatory cells.

Non-Human Primate Studies

The purpose of this study was to determine the toxicity andtoxicokinetic profile of LT1009 when administered to Cynomolgus monkeysin a GLP 28-day safety toxicology study conducted by an independentcontract laboratory organization, LAB Research, Inc. LT1009 wasadministered by 30-minute intravenous infusion every third day for 28days (10 doses). LT1009 was formulated in vehicle containing 20 mMsodium phosphate, 148 mM sodium chloride, 0.02% polysorbate-80, pH=6.5for i.v. administration at doses of 3, 10, 30 and 100 mg/kg; Fortoxicological assessment, blood samples were collected from all animalsat several timepoints on Days 1, 16 and 28. In addition, blood wascollected from recovery animals 48, 72, 144 and 240 hours following theend of the last dose. Parameters monitored during this study includedmortality, clinical signs, body weight, qualitative evaluation of thefood consumption, ophthalmology, electrocardiography, and clinicalpathology (hematology, clinical chemistry, coagulation and urinalysis).Blood samples were also collected for immunophenotyping assessments, atpre-treatment, on the last day of treatment, and on days 35, 42 and atthe end of the recovery period. At termination, a macroscopicexamination was performed and selected organs were weighed. Histologicalevaluation of tissues was conducted on all animals.

There was no mortality, treatment-related adverse clinical signs, ortoxicologically-significant effects on body weight, ophthalmology orelectrocardiography results, or clinical pathology (hematology,coagulation, clinical chemistry and urinalysis) during this study. Therewere no organ weight changes or macroscopic or microscopic findings toindicate an adverse effect of LT1009. LT1009 formulation every third dayover 28 days (10 treatments) to Cynomolgus monkeys, at dose levels of 3,10, 30 and 100 mg/kg was well tolerated and did not result in anytoxicologically significant changes. As such, the No Observed ToxicEffect Level (NOTEL) for LT1009 in this study was considered to be 100mg/kg.

However, there were significant (p<0.001) reductions in peripheral bloodlymphocyte counts at the high dose only (100 mg/kg). Of the 10 animalsin the 100 mg/kg cohort, the mean lymphocyte counts (10⁹ cells/L±SD)were 5.61±2.24 before treatment, and were significantly (p<0.001)reduced to 3.18±1.25 (n=10) when males (n=5) and females (n=5) werecombined for the analysis. This change was reversed during 7 days ofrecovery and was not considered adverse under the conditions of thestudy. No test-article related effect was observed on lymphocytesubpopulations following administration of LT1009 at dose level up toand including 30 mg/kg, or apparent relationship between the LT1009administration and the absolute number of B and NK cells at any of thedose levels tested. On Day 28, the absolute number of T cells showed astatistically significant decrease following administration of 100 mg/kgLT1009 formulation in both males and females, consistent with thereductions in lymphocyte counts. Analysis of the two main T-cellsubsets, T-helper (CD4) and T-cytotoxic (CD8), indicated that theobserved reduction in T cells was correlated with a decrease in theabsolute number of T-helper cells, whereas the T cytotoxic cells werenot affected.

These mouse and primate studies indicate that anti-S1P antibodytreatment can reduce lymphocyte counts. These findings are consistentwith the scientific literature suggesting that S1P is involved inlymphocyte trafficking and egress from primary and secondary lymphoidtissue into the peripheral circulation. Consequently in humans, it ispossible that changes in lymphocyte counts could be a pharmocodynamicmarker that could indicate in vivo biological activity of the humanizedLT1009 drug candidate formulated for systemic administration. Further,it is possible that systemic administration of LT1009 could be used toalter lymphocyte trafficking with resulting lymphopenia necessary forthe treatment of multiple sclerosis or other disorders which mightbenefit from reduced peripheral blood lymphocyte counts.

Example 29 Purification of LT1009 Antibody with Low S1P Carry-Over

Generating highly pure, highly qualified antibodies for pre-clinical orclinical use is of paramount importance for therapeutic drugdevelopment. In addition to being free of cellular proteins, DNA andviruses, the antibody preparation should also not contain any of theantigen, so the antibody is fully active and able to bind its targetwhen administered to a patient. Normally, purification and formulationof an antibody removes the antigen, but after purification of theanti-sphingosine-1-phosphate (S1P) monoclonal antibody, LT1009, Lpathsometimes observes significant levels of S1P carried over from theantibody production. S1P is a bioactive lipid that is synthesized bymammalian cells, including Chinese Hamster Ovary (CHO) cells. Duringproduction of LT1009, e.g., from the transfected CHO cell line LH1 275(ATCC Accession No. PTA-8422), intracellular pools of S1P can bereleased into the media as a result of normal cellular signaling and/oras a consequence of cell rupture after cell death. The LT1009 antibodyexpressed in the cell-conditioned medium (supernatant) is able to bindto this S1P. As production continues, more S1P may be released andaccumulate in the supernatant as a complex with LT1009.While not wishingto be bound by theory, it is believed that the more time the antibodyhas in contact with the S1P in the medium, the more of thatextracellular S1P would be bound to the LT1009 and carried over into theantibody preparation. When produced in CHO cells, LT1009 antibodypreparations may contain in excess of 0.5 moles (50 mole percent, mol %)of S1P per mole of antibody. Thus in order to reduce the amount of S1Pcarry-over, steps must be taken in both upstream and downstreamprocessing to minimize the amount of S1P in the crude harvest and topromote removal of that S1P during purification.

S1P Quantification Methods:

The S1P concentrations in various preparations of the LT1009 antibodywere measured at WindRose Analytica by RP-HPLC-MS-MS method. Massspectrometry is rapid and sensitive and, if applied properly, canquantify picogram amounts of analyte. The approach taken in thisanalytical method is to introduce the S1P into an electrospray massspectrometer source by reversed phase liquid chromatography (RPC). TheRPC step separates the S1P from protein, salts and other contaminants.Following the chromatographic step the S1P is ionized in the source andpassed onto an ion trap mass analyzer. All ions except those of theappropriate mass-to-charge ratio (m/z=380) are ejected from the trap.The remaining ions are fragmented in the ion trap and a specificdaughter ion (m/z=264) is monitored. The results verify sample identityin three dimensions of analysis: RPC retention time, parent ion m/z of380, and daughter ion m/z of 264. It is unlikely that any other compoundwould satisfy all three of these criteria. Additionally, the MS-MS stepmaximizes signal-to-noise and therefore increases sensitivitysignificantly. Since there is no extraction step required there is noneed for an internal standard. Additionally, the direct injection ofsample into the HPLC-MS increases recovery and sensitivity and decreasescomplexity and analysis time.

For comparison, the concentration of S1P in extracts of selectedantibody preparations was determined using a S1P-quantification ELISA. A4-fold excess of 1:2 chloroform:methanol was added to 1 mg/ml antibodysamples to extract the S1P. The aqueous/organic solution was extensivelyvortexed and sonicated to disrupt antibody-lipid complexes and incubatedon ice. After centrifugation, the soluble fraction was evaporated usinga speed-vac, and the dried S1P was resuspened in delipidated humanserum. The S1P concentration in the resuspended sample was determined bya competitive ELISA using an anti-S1P antibody and a S1P-coatingconjugate. The coating conjugate, a covalently linked S1P-BSA, wasprepared by coupling a chemically synthesized thiolated S1P withmaleimide-activated BSA. For the S1P standard, mono-layer S1P wassolubilized in 1% BSA in PBS (137 mM NaCl, 2.68 mM KCl, 10.1 mM Na2HPO4,1.76 mM KH2PO4; pH 7.4) by sonication to obtain 10 uM S1P (S1P-BSAcomplex). The S1P-BSA complex solution was further diluted withdelipidated human serum to appropriate concentrations (up to 2 uM).Microtiter ELISA plates (Costar, high-binding plate) were coated withS1P-coating material diluted in 0.1 M sodium carbonate buffer (pH 9.5)at 37° C. for 1 hour. Plates were washed with PBS and blocked withPBS/1% BSA/0.1% Tween-20 for 1 hr at room temperature. For the primaryincubation, 0.4 ug/mL biotin-labeled anti-S1P antibody, designatedamounts of S1P-BSA complex and samples to be tested were added to wellsof the ELISA plates. After 1 hour-incubation at room temperature, plateswere washed followed by incubation with 100 ul per well of HRPconjugated streptavidin (1:20,000 dilution) for 1 hour at roomtemperature. After washing, the peroxidase reaction was developed withTMB substrate and stopped by adding 1 M H2SO4. The optical density wasmeasured at 450 nm using a Thermo Multiskan EX.

Upstream Processing to Minimize S1P:

For upstream processing, culturing the CHO cells in serum-free medium(Invitrogen, Cat #10743-029) is essential because serum containscontaminating S1P that could add to that produced by the CHO cellsthemselves. In addition to use of serum-free medium, harvesting theantibody from the bioreactor prior to extensive cell death will preventintracellular pools of S1P to be released into the medium. Finally,initiating the downstream processing immediately after harvest minimizesthe time the LT1009 spends in the presence of S1P and the amount oflipid carried over to the final preparation. Despite attempts tominimize the S1P levels during upstream processing, significant S1Poften remains in the crude harvest which typically ranges between0.1-0.2 molar ratio (10-20 mol %) of bound S1P per mol of antibody.

Therefore, Lpath developed downstream methods to remove lipids fromantibody preparations in order to generate LT1009 material with very lowS1P carry-over levels. These methods (described immediately below) weredeveloped by Lpath and transferred to Laureate Pharma, Inc. toincorporate into their processing methods. As a result, the final drugproduct produced by Laureate has very low levels of bound S1P (<0.4 mol% measured by HPLC-MS-MS).

Downstream Processing to Reduce S1P:

Traditionally, purification of antibodies from cultured supernatant orascites fluid involves affinity chromatography. This one-step methodsuses recombinant protein-A covalently bond to highly cross-linkedagarose (GE healthcare, Cat No 17-5199-04). The protein-A acts as aligand for Fc domains of monoclonal antibodies. Since the protein-A andS1P binding sites are distinct, S1P does not displace when LT1009 bindsthe protein-A resin. The high affinity for LT1009 and low solubility inaqueous buffers ensures that S1P remains associated with LT1009 eventhrough extensive washes with high salt buffers (see below). Therefore,conventional antibody purification process that included: Protein AChromatography, Low pH Viral Inactivation, followed by Neutralization, QAnion Exchange Chromatography, Viral Nanofiltration and FinalUltrafiltration/Diafiltration did not remove co-purified (bound toLT1009) S1P. In order to dissociate S1P from the bound LT1009, Lpathexploits a special feature in the mechanism of binding.

Lpath in-house research demonstrated that S1P binding activity of LT1009was reduced at pH<4.0, or at pH>8.5. However, conducting Protein Achromatography at pH<4.0 in order to reduce bound S1P was not feasiblebecause antibody will not bind to Protein A resin at such low pH.Therefore, high salt, pH 8.5 wash step was incorporated in protein Achromatography to reduce S1P bound to LT1009. Further studiesdemonstrated that the high salt buffer (650 mM NaCl) and 50 mM SodiumPhosphate buffer pH 8.5 did not effectively remove S1P from LT1009.Further increasing of salt concentration from 0.65 M to 1 M (pH 8.5) andextending of the high salt wash step from four column volumes to fivecolumn volumes did not yield product with lower bound S1P.

Use of metal chelators to remove S1P: Lpath developed a method thatinvolved premixing of two volumes of crude LT1009 antibody harvest,produced from CHO cells bioreactor campaign, with one volume of ProteinA IgG binding buffer (“Pierce binding buffer,” Pierce Protein ResearchProducts, Thermo Fisher Scientific, Rockford Ill.), containing 50 mMPotassium Phosphate, 1M NaCl, 2 mM EDTA and 5% glycerol, pH 8.0.According to this procedure the Protein A column was equilibrated withPierce binding buffer, loaded with premixed crude harvest and washedwith 10 column volumes of the same binding buffer. The resultingpurified LT1009 contained 2-fold less mole percent of S1P as judged bythe S1P-quantification ELISA.

It is currently believed that a metal ion chelator (e.g., EDTA) isimportant or even essential for effective reduction of S1P carryover inLT1009 antibody preparations. Indeed, titration of LT1009 with EDTA,which chelates divalent metal cations, abrogates S1P binding (FIG. 14).The ability of EDTA to dissociate S1P from LT1009 is believed tofacilitate removal of S1P during purification of LT1009. Addition of 2mM EDTA in the binding and washing buffers effectively lowered the S1Pcarryover twofold in the eluted antibody fractions. It should be notedthat the S1P levels in this study are relatively low initially, andincluding EDTA should produce greater reduction in lipid carryover insamples with higher initial S1P levels. Without being limited by thefollowing examples, other metal chelators such as EGTA, histidine,malate and phytochelatin may be useful in dissociating S1P from theantibody. EGTA and EDTA are presently preferred divalent metal chelatorsfor separating S1P from anti-S1P antibodies.

Based on the listed (on the MSDS) chemical ingredients in Pierce IgGbinding buffer, a new high salt buffer was developed by Lpath that wascomparable in pH and conductivity to the Pierce buffer, and the newpremixing step was incorporated in the LT1009 manufacturing process.

Current Downstream Purification Process Includes:

-   -   Premixing of crude harvest with 4× potassium high salt EDTA        buffer (200 mM KPi, 4M NaCl, 8 mM EDTA, 20% glycerol, pH 8.0) in        ratio of 2 L crude harvest to 0.182 L KPi high salt-EDTA buffer.        This step is intended to disrupt and dissociate S1P from LT1009    -   Capture of Crude Harvest-High Salt mix on Protein A column and        washing the column with 10 column volumes of High Salt-EDTA        buffer to remove S1P    -   Elution of LT1009 from Protein A resin at low pH (3.6-3.8)    -   Low pH hold of Protein A Eluate at pH 3.6-3.8 for a viral        inactivation followed by neutralization of the eluate to neutral        pH    -   Sartobind Q anion exchange chromatography to remove residual        host cell proteins and nucleotides, as well as any leached        protein A.    -   Nanofiltration using Virosart CPV nanofilter as an additional        step for virus removal    -   Final UF/DF filtration for protein concentration and final        formulation

Use of low pH and C8 resins to remove S1P: In addition to the use ofmetal chelators such as EDTA during the purification, one can alsoexploit the hydrophobic nature of S1P to remove the lipid from purifiedantibody preparations. This method involves a two-step process: 1)dissociation of the lipid from the antibody, and 2) physical separationof the lipid from the aqueous environment. The applicant employs a pHinduced Lipid removal (pHiL) treatment as an easy, robust method topromote dissociation from antibody preparations. Antibodies generallyexhibit markedly reduced antigen-binding affinity at low pH. Antibodiesgenerated against phospholipids (e.g. S1P and LPA) fail to bind lipidsat pH 3.0-3.5, depending on the specific antibody and the lipid (FIG.14). In determining the correct pH to promote dissociation, a pHtitration experiment should be performed to determine the pH thatabrogates binding yet maintains an intact IgG, such that bindingactivity is restored once the pH is increased. Once this pH has beendetermined, the antibody is dialyzed against buffer below the criticalpH (e.g. 50 mM sodium acetate, pH 3.0-3.5) at 4° C. Under theseconditions, both the lipid and antibody exist as isolated components insolution. The dialyzed solution is passed through a material, such as C8silica resin (e.g., SepPak cartridges, Waters, Cat no WAT036775), thatbinds the lipid and facilitates separation of the protein free of lipid.As a consequence, the free lipid irreversibly binds the hydrophobicresin (in the case of C8 silica resin) while the antibody flows throughwithout significant loss (˜90% recovery). Most of the lipid can beremoved with one pass through the cartridge, but modest gains in lipidremoval can be achieved with an additional pass (Table 12).

The metal chelation and pHiL methods described above can easily beincorporated into a single purification procedure. EDTA is compatiblewith most buffers and does not adversely affect antibody stability,solubility or protein-A binding. During purification, washing the boundIgG with copious amount of EDTA-containing buffer will remove a portionof the S1P from the S1P-LT1009 complex as well as potentially dissociateother metal-dependant antigens-antibody complexes. If the EDTA wash doesnot sufficiently remove the lipid, the eluate from the protein-A columncan be treated using the pHiL method. Elution of bound IgG fromprotein-A is typically achieved using low pH buffers (pH<3.0). If theanti-lipid antibody elutes from the column at a pH or below the criticalpH for lipid binding, the sample can simply be applied to the C8 silicaresin to remove the lipid. If necessary, the pH can be easily adjustedprior to applying it to the resin.

TABLE 12 Lipid removal using pHiL method Mole percent of lipid in sample(relative to amount of antibody) Antibody Recovery Monoclonal BeforeAfter 1^(st) After 2^(nd) % Yield (after Antibody treatment treatmenttreatment 1^(st) treatment) Murine 60% 6.3% 0.97% 88% Anti-S1P Humanized46% 4.3% 0.81% 89% Anti-S1P Humanized 14 4.5 6.0 91% Anti-LPA

Example 30 Formulations Containing the Humanized Monoclonal AntibodyLT1009

1. Introduction

This example describes experiments to assess the stability of severalformulations containing the humanized monoclonal antibody LT1009, whichis reactive against the bioactive signaling lipid sphingosine1-phosphate (S1P). LT1009 is an engineered full-length IgG1k isotypeantibody that contains two identical light chains and two identicalheavy chains, and has a total molecular weight of about 150 kDa. Thecomplementarity determining regions (CDRs) of the light and heavy chainswere derived from a murine monoclonal antibody generated against S1P,and further include a Cys to Ala substitution in one of the CDRs. InLT1009, human framework regions contribute approximately 95% of thetotal amino acid sequences in the antibody, which binds S1P with highaffinity and specificity.

The purpose of the testing described in this example was to develop oneor more preferred formulations suitable for systemic administration thatare capable of maintaining stability and bioactivity of LT1009 overtime. As is known, maintenance of molecular conformation, and hencestability, is dependent at least in part on the molecular environment ofthe protein and on storage conditions. Preferred formulations should notonly stabilize the antibody, but also be tolerated by patients wheninjected. Accordingly, in this study the various formulations testedincluded either 11 mg/mL or 42 mg/mL of LT1009, as well as different pH,salt, and nonionic surfactant concentrations. Additionally, threedifferent storage temperatures (5° C., 25° C., and 40° C.) were alsoexamined (representing actual, accelerated, and temperature stressconditions, respectively). Stability was assessed using representativesamples taken from the various formulations at five different timepoints: at study initiation and after two weeks, 1 month, 2 months, and3 months. At each time point, testing involved visual inspection,syringeability (by pulling through a 30-gauge needle), and sizeexclusion high performance liquid chromatography (SE-HPLC). Circulardichroism (CD) spectroscopy was also used to assess protein stabilitysince above a certain temperature, proteins undergo denaturation,followed by some degree of aggregate formation. The observed transitionis referred to as an apparent denaturation or “melting” temperature(T_(m)) and indicate the relative stability of a protein.

2. Materials and Methods

a. LT1009

The formulation samples (˜0.6 mL each) were generated from an aqueousstock solution containing 42 mg/mL LT1009 in 24 mM sodium phosphate, 148mM NaCl, pH 6.5. Samples containing 11 mg/mL LT1009 were prepared bydiluting a volume of aqueous stock solution to the desired concentrationusing a 24 mM sodium phosphate, 148 mM NaCl, pH 6.5, solution. Toprepare samples having the different pH values, the pH of eachconcentration of LT1009 (11 mg/mL and 42 mg/mL) was adjusted to 6.0 or7.0 with 0.1 M HCl or 0.1 M NaOH, respectively, from the original 6.5value. To prepare samples having different NaCl concentrations, 5 M NaClwas added to the samples to bring the salt concentration to either 300mM or 450 mM from the original 148 mM. To prepare samples havingdifferent concentrations of nonionic surfactant, polysorbate-80 wasadded to the samples to a final concentration of either 200 ppm or 500ppm. All samples were aseptically filtered through 0.22 μm PVDF membranesyringe filters into sterile, depyrogenated 10 mL serum vials. The vialswere each then sealed with a non-shedding PTFE-lined stopper that wassecured in place and protected from contamination with a crimped on cap.Prior to placement into stability chambers, the vials were brieflystored at 2-8° C.; thereafter, they were placed upright in a stabilitychamber adjusted to one of three specified storage conditions: 40°C.(±2° C.)/75%(±5%) relative humidity (RH); 25° C.(±2° C.)/60%(±5%) RH;or 5° C.(±3° C.)/ambient RH. A summary of the formulation variablestested appears in Table 13, below.

TABLE 13 Formulation Summary LT1009, 11 mg/mL LT1009, 42 mg/mLPolysorbate 80 NaCl pH Polysorbate 80 NaCl pH 0.02% 148 mM 7 0.02% 148mM 7 Polysorbate NaCl 6.5 Polysorbate NaCl 6.5 6 6 300 mM 7 300 mM 7NaCl 6.5 NaCl 6.5 6 6 450 mM 7 450 mM 7 NaCl 6.5 NaCl 6.5 6 6 0.05% 148mM 7 0.05% 148 mM 7 Polysorbate NaCl 6.5 Polysorbate NaCl 6.5 6 6 300 mM7 300 mM 7 NaCl 6.5 NaCl 6.5 6 6 450 mM 7 450 mM 7 NaCl 6.5 NaCl 6.5 6 6

b. Taking of Samples

Samples of each formulation were analyzed according to the schedulelisted in Table 14, below. One vial was used for each storage conditionfor all time points. On a date when samples were to be taken, vials werepulled from each stability chamber and 150 μL of each sample weretransferred into correspondingly labeled separate vials that were placedon the bench for 1 hour prior to testing. The original vial wasimmediately placed back into the specified stability chamber afterwithdrawing the aliquot to be tested.

TABLE 14 Drug Product Formulation Study Stability Matrix StorageIntervals (months) Conditions T = 0 0.5 1 2 3 Protein ConcentrationLT1009, 11 mg/mL 40° C. x, y x, y x x x, y 25° C. x, y x x x, y  5° C.x, y x x x, y Protein Concentration LT1009, 42 mg/mL 40° C. x, y x, y xx x, y 25° C. x, y x x x, y  5° C. x, y x x x, y x = Appearance, pH,SDS-PAGE, SE-HPLC, UV OD-280, IEF y = Syringeability (performed byaseptically drawing 200 μL of a sample with a 30-gauge needle connectedto a disposable 1-mL syringe)

c. Analytical Procedures

For a given time point, aliquots from each sample were subjected to aseries of standard analyses, including visual inspection,syringeability, pH, SDS-PAGE (under both reducing and non-reducingconditions), SE-HPLC, and IEF. Protein concentrations were determined byUV spectroscopy (OD-280). Circular dichroism (CD) studies were alsoperformed.

Circular dichroism spectroscopy was performed separately from theformulation studies. An Aviv 202 CD spectrophotometer was used toperform these analyses. Near UV CD spectra were collected from 400 nm to250 nm. In this region, the disulfides and aromatic side chainscontribute to the CD signals. In the far UV wavelength region (250-190nm), the spectra are dominated by the peptide backbone. Thermaldenaturation curves were generated by monitoring at 205 nm, a wavelengthcommonly used for b-sheet proteins. Data was collected using 0.1 mg/mlsamples with heating from 25° C. to 85° C. Data were collected in 1° C.increments. The total time for such a denaturation scan was between 70and 90 minutes. The averaging time was 2 seconds.

3. Results and Discussion

For all samples analyzed, visual appearance did not change over time.Likewise, syringeability testing demonstrated that samples could bepulled into a syringe equipped with a 30-gauge needle withoutdifficulty. The results of the various analytical tests were consistent,and SE-HPLC was determined to be an excellent stability-indicatingmethod for LT1009. These results showed that increasing saltconcentration reduced both the generation of aggregates and thegeneration of smaller non-aggregate impurities. It was also found thatdecreasing pH also reduced aggregate and impurity formation. Inaddition, it was determined that increasing the polysorbate-80concentration above 200 ppm did not further stabilize LT1009. FIG. 15illustrates the results of the SE-HPLC experiments performed on samplescontaining 11 mg/mL LT1009. Comparable results were obtained for samplescontaining 42 mg/mL LT1009, although lower LT1009 concentrations showedless potential for aggregate formation as compared to the higherconcentration, indicating that the antibody appeared to be slightly lessstable under all conditions tested at the higher concentration.

From the circular dichroism studies, it was found that LT1009 adopts awell-defined tertiary structure in aqueous solution, with well-orderedenvironments around both Tyr and Trp residues. It also appeared that atleast some of the disulfides in antibody molecules experience somedegree of bond strain, although this is not uncommon when both intra-and inter-chain disulfides are present. The secondary structure ofLT1009 was found to be unremarkable, and exhibited a far UV CD spectrumconsistent with B-sheet structure. The observed transition is referredto as an apparent denaturation or “melting” temperature (T_(m)). Uponheating, LT1009 displayed an apparent T_(m) of approximately 73° C. atpH 7.2. The apparent T_(m) increased to about 77° C. at pH 6.0. Theseresults indicate that a slightly acidic pH could enhance long-termstability of aqueous formulations of LT1009. Addition of NaCl and/orpolysorbate-80 also provided additional stabilization.

Together, the data from these experiments indicate that LT1009 is moststable around pH 6 and 450 mM NaCl independent of antibodyconcentration. Indeed, SE-HPLC testing indicated that increasing thesalt concentration to 450 mM and decreasing the pH to 6.0 whilemaintaining the polysorbate-80 concentration at 200 ppm had a verybeneficial effect on the stability of LT1009. Inclusion ofpolysorbate-80 above 200 ppm had no further mitigating effect againstaggregate formation, probably because it was already above its criticalmicelle concentration at 200 ppm. While not wishing to be bound by anyparticular theory, the fact that aggregate formation in LT1009 wasreduced with increasing salt concentration under the studied conditionscould indicate that aggregate formation is at least in part based moreon ionic interactions between molecules rather than hydrophobicinteractions. The observation that lowering the pH from 7 to 6 alsoreduces aggregate formation could be explained by reduced hydrophobicityof the amino acid histidine at the lower pH. Finally, the observedincreased tendency of aggregate formation at increased LT11009concentration can simply be explained by the greater chance of moleculeshitting each other at the right time at the right place for aggregateformation.

As these experiments show, a preferred aqueous LT1009 formulation is onehaving 24 mM phosphate, 450 mM NaCl, 200 ppm polysorbate-80, pH 6.1. Therelatively high tonicity of this formulation should not pose a problemfor systemic applications since the drug product will likely be dilutedby injection into iv-bags containing a larger volume of PBS prior toadministration to a patient.

All of the compositions and methods described and claimed herein can bemade and executed without undue experimentation in light of the presentdisclosure. While the compositions and methods of this invention havebeen described in terms of preferred embodiments, it will be apparent tothose of skill in the art that variations may be applied to thecompositions and methods. All such similar substitutes and modificationsapparent to those skilled in the art are deemed to be within the spiritand scope of the invention as defined by the appended claims.

All patents, patent applications, and publications mentioned in thespecification are indicative of the levels of those of ordinary skill inthe art to which the invention pertains. All patents, patentapplications, and publications, including those to which priority oranother benefit is claimed, are herein incorporated by reference to thesame extent as if each individual publication was specifically andindividually indicated to be incorporated by reference.

The invention illustratively described herein suitably may be practicedin the absence of any element(s) not specifically disclosed herein.Thus, for example, in each instance herein any of the terms“comprising”, “consisting essentially of”, and “consisting of” may bereplaced with either of the other two terms. The terms and expressionswhich have been employed are used as terms of description and not oflimitation, and there is no intention that in the use of such terms andexpressions of excluding any equivalents of the features shown anddescribed or portions thereof, but it is recognized that variousmodifications are possible within the scope of the invention claimed.Thus, it should be understood that although the present invention hasbeen specifically disclosed by preferred embodiments and optionalfeatures, modification and variation of the concepts herein disclosedmay be resorted to by those skilled in the art, and that suchmodifications and variations are considered to be within the scope ofthis invention as defined by the appended claims.

1. An isolated humanized antibody, or an antigen binding fragmentthereof, specifically reactive with S1P and comprising at least oneheavy chain and at least one light chain, wherein: A. each heavy chaincomprises a heavy chain variable domain comprising: (i) a sequence ofamino acid residues having an amino acid sequence [SEQ ID NO: 27]EVQLVQSGAEVKKPGESLKISCQSFGYIFIDHTIHWMRQMPGQGLEWMGAISPRHDITKYNEMFRGQVTISADKSSSTAYLQWSSLKASDTAMYFCARGGFYGSTIWFDF WGQGTMVTVSS; or

(ii) a sequence of amino acid residues having at least about 80%sequence identity to the amino acid sequence of A(i), above; and B. eachlight chain comprises a light chain variable domain comprising: (i) asequence of amino acid residues having an amino acid sequence [SEQ IDNO: 29] ETTVTQSPSFLSASVGDRVTITCITTTDIDDDMNWFQQEPGKAPKLLISEGNILRPGVPSRFSSSGYGTDFTLTISKLQPEDF ATYYCLQSDNLPFTFGQGTKLEIK; or

(ii) a sequence of amino acid residues having at least about 80%sequence identity to the amino acid sequence of B(i), above, optionallywherein the antibody or antigen binding fragment thereof has two heavychains and two light chains.
 2. An isolated humanized antibody, or anantigen binding fragment thereof, according to claim 1, wherein: A. eachheavy chain comprises at least one of the following: (i) a firstsequence of amino acid residues of sequence DHTIH [SEQ ID NO:13]; (ii) asecond sequence of amino acid residues AISPRHDITKYNEMFRG [SEQ ID NO:18];or (iii) a third sequence of amino acid residues of sequenceGGFYGSTIWFDF [SEQ ID NO: 15]; and B. each light chain comprises at leastone of the following: (i) a first sequence of amino acid residues ofsequence ITTTDIDDDMN [SEQ ID NO: 10]; (ii) a second sequence of aminoacid residues of sequence EGNILRP [SEQ ID NO:11]; or (iii) a thirdsequence of amino acid residues of sequence LQSDNLPFT [SEQ ID NO:12]. 3.An isolated humanized antibody, or an antigen binding fragment thereof,according to claim 1, wherein: A. each heavy chain comprises: (i) afirst sequence of amino acid residues of sequence DHTIH [SEQ ID NO:13];(ii) a second sequence of amino acid residues AISPRHDITKYNEMFRG [SEQ IDNO:18]; and (iii) a third sequence of amino acid residues of sequenceGGFYGSTIWFDF [SEQ ID NO:15]; and B. each light chain comprises: (i) afirst sequence of amino acid residues of sequence ITTTDIDDDMN [SEQ IDNO: 10]; (ii) a second sequence of amino acid residues of sequenceEGNILRP [SEQ ID NO:11]; and (iii) a third sequence of amino acidresidues of sequence LQSDNLPFT [SEQ ID NO: 12].
 4. An isolated humanizedantibody according to claim 1, wherein: A. each heavy chain comprises asequence of amino acid residues having an amino acid sequence: (i) [SEQID NO: 31] EVQLVQSGAEVKKPGESLKISCQSFGYIFIDHTIHWMRQMPGQGLEWMGAISPRHDITKYNEMFRGQVTISADKSSSTAYLQ WSSLKASDTAMYFCARGGFYGSTIWFDFWGQGTMVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNS TYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLS PGK; or

(ii) a sequence of amino acid residues having at least about 80%sequence identity to the amino acid sequence of A(i), above; and B. eachlight chain comprises a sequence of amino acid residues having an aminoacid sequence: (i) [SEQ ID NO:32]ETTVTQSPSFLSASVGDRVTITCITTTDIDDDMNWFQQEPGKAPKLLISEGNILRPGVPSRFSSSGYGTDFTLTISKLQPEDFATYYCLQSDNLPFTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACE VTHQGLSSPVTKSFNRGEC; or

(ii) a sequence of amino acid residues having at least about 80%sequence identity to the amino acid sequence of B(i), above.
 5. Anisolated humanized antibody, or an antigen binding fragment thereof,according to claim 4, wherein: A. each heavy chain comprises at leastone of the following: (i) a first sequence of amino acid residues ofsequence DHTIH [SEQ ID NO: 13]; (ii) a second sequence of amino acidresidues AISPRHDITKYNEMFRG [SEQ ID NO: 18]; or (iii) a third sequence ofamino acid residues of sequence GGFYGSTIWFDF [SEQ ID NO: 15]; and B.each light chain comprises at least one of the following: (i) a firstsequence of amino acid residues of sequence ITTTDIDDDMN [SEQ ID NO: 10];(ii) a second sequence of amino acid residues of sequence EGNILRP [SEQID NO: 11]; or (iii) a third sequence of amino acid residues of sequenceLQSDNLPFT [SEQ ID NO: 12].
 6. An isolated humanized antibody, or anantigen binding fragment thereof, according to claim 4, wherein: A. eachheavy chain sequence comprises: (i) a first sequence of amino acidresidues of sequence DHTIH [SEQ ID NO:13]; (ii) a second sequence ofamino acid residues AISPRHDITKYNEMFRG [SEQ ID NO: 18]; and (iii) a thirdsequence of amino acid residues of sequence GGFYGSTIWFDF [SEQ ID NO:15]; and B. each light chain sequence comprises: (i) a first sequence ofamino acid residues of sequence ITTTDIDDDMN [SEQ ID NO:10]; (ii) asecond sequence of amino acid residues of sequence EGNILRP [SEQ IDNO:11]; and (iii) a third sequence of amino acid residues of sequenceLQSDNLPFT [SEQ ID NO:12].
 7. An isolated humanized antibody according toclaim 1, wherein: A. each heavy chain comprises a sequence of amino acidresidues having an amino acid sequence [SEQ ID NO: 31]EVQLVQSGAEVKKPGESLKISCQSFGYIFIDHTIHWMRQMPGQGLEWMGAISPRHDITKYNEMFRGQVTISADKSSSTAYLQWSSLKASDTAMYFCARGGFYGSTIWFDFWGQGTMVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK; and

B. each light chain comprises a sequence of amino acid residues havingan amino acid sequence [SEQ ID NO: 32]ETTVTQSPSFLSASVGDRVTITCITTTDIDDDMNWFQQEPGKAPKLLISEGNILRPGVPSRFSSSGYGTDFTLTISKLQPEDFATYYCLQSDNLPFTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYA CEVTHQGLSSPVTKSFNRGEC.


8. An isolated humanized antibody according to claim 4, wherein eachheavy chain comprises a sequence of amino acid residues having an aminoacid sequence [SEQ ID NO: 35]EVQLVQSGAEVKKPGESLKISCQSFGYIFIDHTIHWMRQMPGQGLEWMGAISPRHDITKYNEMFRGQVTISADKSSSTAYLQWSSLKASDTAMYFCARGGFYGSTIWFDFWGQGTMVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYT QKSLSLSPG.


9. An isolated humanized antibody, or an antigen binding fragmentthereof, according to claim 1, wherein: A. each heavy chain comprisesthe same heavy chain variable domain amino acid sequence as the heavychain variable domain encoded by the heavy chain gene in vector pATH1009in ATCC Accession No. PTA-8421; and B. each light chain comprises thesame light chain variable domain amino acid sequence as the light chainvariable domain encoded by the light chain gene in vector pATH1009 inATCC Accession No. PTA-8421.
 10. An isolated humanized antibody, or anantigen binding fragment thereof, according to claim 1 wherein at leastone amino acid residue of the antibody is glycosylated.
 11. Apharmaceutical composition comprising an isolated humanized antibody, oran antigen binding fragment thereof, according to claim 1 and apharmaceutically acceptable carrier.
 12. An isolated nucleic acidcomposition that codes for the expression of a humanized antibody orantigen binding fragment thereof according to claim 1, wherein thecomposition comprises: A. a first expression cassette that comprises apromoter and a gene that encodes the heavy chain polypeptide(s) of thehumanized antibody or antigen binding fragment thereof, and B. a secondexpression cassette that comprises a promoter and a gene that encodesthe light chain polypeptide(s) of the humanized antibody or antigenbinding fragment thereof.
 13. An isolated nucleic acid compositionaccording to claim 12, wherein the composition comprises a plasmidcomprising the first and second expression cassettes.
 14. A host celltransfected with an isolated nucleic acid composition according to claim12, optionally a host cell as deposited under accession number ATCCPTA-8421.
 15. A method of treating a disease or disorder in a subjectcomprising administering to a subject in need of such treatment anisolated humanized antibody, or an antigen binding fragment thereof,according to claim 1, wherein said disease or disorder is correlatedwith an aberrant level of S1P,
 16. An isolated humanized antibody, or anantigen binding fragment thereof, according to claim 1, wherein: A. eachheavy chain comprises the same heavy chain as the heavy chain of theantibody expressed by CHO cell line LH1 275, as deposited underaccession number ATCC PTA-8422; and B. each light chain comprises thesame light chain as the light chain of the antibody expressed by CHOcell line LH1 275, as deposited under accession number ATCC PTA-8422.17. An isolated humanized antibody specifically reactive with S1P, whichcomprises a humanized light chain variable domain includinghypervariable complementarity determining regions (CDR's) characterizedby CDRL1 (SEQ ID NO: 10), CDRL2 (SEQ ID NO: 11), and CDRL3 (SEQ ID NO:12), and a humanized heavy chain variable domain including hypervariableCDR's characterized by CDRH1 (SEQ ID NO: 13), CDRH2 (SEQ ID NO: 18), andCDRH3 (SEQ ID NO: 15).
 18. An isolated nucleic acid composition thatencodes a humanized antibody specifically reactive with S1P, wherein thecomposition comprises a first gene that encodes a light chain gene thatcodes for CDR peptides of SEQ ID NO: 10, SEQ ID NO: 11, and SEQ ID NO:12 and a second gene that encodes a heavy chain gene that codes for SEQID NO: 13, SEQ ID NO: 18, and SEQ ID NO:
 15. 19. A plasmid comprising anisolated nucleic acid composition according to claim 18, wherein saidplasmid optionally encodes a humanized antibody that is specificallyreactive with S1P and which comprises a heavy chain gene including thenucleic acid sequence of SEQ ID NO: 33 and a light chain gene includingthe light chain nucleic acid sequence of SEQ ID NO:
 34. 20. Arecombinant host cell transfected with a plasmid according to claim 19and capable of expressing said antibody, wherein said host cell isoptionally a CHOK1SV cell, optionally a cell line having the designationLH1 275, and deposited under accession number ATCC PTA-8422.